Amazon FBA Inbound Placement Fee 2026: The PBI3 Closure Changes the Math in 31 Days

Amazon’s FBA inbound placement fee — the per-unit charge Amazon assesses when a seller sends inventory to fewer fulfillment centers than Amazon’s network algorithm wants it distributed across — increased again on January 15, 2026, and is about to be disrupted again on September 17, 2026, when the permanent closure of the PBI3 fulfillment center in Port St. Lucie, Florida forces Amazon to rebalance inventory placement across its Southeast network, recalculate default inbound splits for Florida-heavy SKUs, and reassign those units to Georgia and Alabama nodes that will produce different placement fee calculations than every seller’s current shipment plans assume.

The practical consequence hits in two directions simultaneously.

Sellers sending Q4 inventory to FBA right now — during the most important inbound window of the year — are building shipment plans against a network topology that changes in 31 days. A placement fee estimate shown in Seller Central today may not match the actual charge applied when the next shipment is received, because Amazon’s inbound placement algorithm will be operating on a reconfigured Southeast node map after September 17.

Sellers who have inventory currently at PBI3, in transit to PBI3, or whose historical placement patterns included PBI3 as a primary Southeast node will see placement fee volatility not explained by any change in their own shipping behavior. This guide covers exactly how Amazon’s inbound placement fee works in 2026, what the PBI3 closure specifically means for sellers’ fee exposure and Prime badge stability, how to identify and challenge placement fee errors that arise from the network rebalancing, and when FBA inventory disputes connected to the closure require legal escalation.

What this guide covers

This guide explains how the 2026 placement fee works, what the PBI3 closure means for fee calculations and Prime badge stability over the next 31 days, how to identify and dispute fee errors that arise from the network rebalancing, and when inventory or fee disputes connected to the closure require legal escalation.

Table of Contents

1. How the FBA Inbound Placement Fee Works in 2026
2. The 2026 Rate Card: What Changed on January 15
3. The PBI3 Closure: What Happens to Your Shipments on September 17
4. If Your Revenue Is Florida-Heavy: What to Do Right Now
5. Prime Badge Instability After the Closure
6. The Q4 Intersection: Why the Timing Is Unusually Bad
7. When Placement Fee Errors Arise From Network Rebalancing
8. FBA Inventory Claims Connected to the PBI3 Closure
9. How to Minimize Placement Fees on Q4 Inbound Shipments
10. Frequently Asked Questions
11. How DAM Law Firm Can Help

How the FBA Inbound Placement Fee Works in 2026

Amazon introduced the FBA Inbound Placement Service Fee in March 2024 to replace the older Inventory Placement Service. The January 2026 update restructured the fee with new weight bands and a new Small Bulky tier. Understanding the mechanics determines whether the fee is unavoidable for a given shipment or whether a logistics adjustment eliminates or reduces it.

The three placement options and their fee implications

When creating an FBA inbound shipment plan in Seller Central, Amazon offers three placement options. Minimal shipment splits — sending inventory to one or a small number of inbound locations — carries the highest per-unit placement fee because Amazon bears the full cost of redistributing the inventory across its network after receiving it. Partial shipment splits — sending to two or three fulfillment centers Amazon designates — carry a reduced per-unit fee. Amazon-optimized splits — sending to four or more fulfillment centers Amazon designates — carry zero placement fee because the seller is doing Amazon’s distribution work. The fee-free optimized split requires coordinating multiple shipments to multiple destinations, which increases inbound freight complexity and cost. Whether the freight savings from optimized splits outweigh the placement fee depends on the specific SKUs, carton counts, product dimensions, and carrier rates.

How Amazon calculates the fee per unit

The placement fee uses two inputs: product size tier (small standard, large standard, small bulky, large bulky, extra large) and shipping weight within that tier. As AMZ Prep’s 2026 placement fee analysis documents, the January 2026 update added a second weight band to small standard products and split the old Large Bulky tier into Small Bulky and Large Bulky, creating five weight bands for large standard items. Sellers who have not recalculated placement fees since the January update may be working from incorrect per-unit estimates. The fee is assessed per unit received — not per shipment — so it scales directly with order quantity.

A seller sending 2,000 units of a large standard product under minimal splits at $0.45 per unit pays $900 in placement fees for that shipment. The same 2,000 units split across four Amazon-designated fulfillment centers pays zero in placement fees, though the freight cost to four locations instead of one must be factored into the net comparison.

The 2026 Rate Card: What Changed on January 15

Three specific changes took effect on January 15, 2026 that affect how the placement fee is calculated for most standard-size products.

Standard-size weight band expansion

Small standard products now have two weight bands rather than one. Products under 4 oz and products between 4 oz and 1 lb carry different per-unit fees — sellers with products near the 4 oz threshold should confirm which band their products fall into, because the band assignment determines which placement fee tier applies.

Large standard products now have five weight bands covering weight ranges from under 1 lb through 20 lbs. The old Large Bulky tier split into Small Bulky and Large Bulky — the overall placement fee for standard-size products increased by an average of $0.05 per unit under the minimal splits option. Sellers running shipment cost models built on 2025 rate card assumptions are underestimating placement fees by $0.05 per unit — which at scale represents meaningful margin erosion that does not appear in the rate card as an obvious increase.

The inbound defect fee consolidation

Amazon consolidated the old separate placement and defect charges into a single inbound defect fee averaging $0.60 per unit for shipments that arrive late, get misrouted, or never arrive as planned. This consolidation matters for the PBI3 closure scenario specifically: inventory in transit to PBI3 on or around September 17 faces misrouting risk as Amazon’s system redirects inbound shipments away from the closing facility. Misrouted shipments trigger the inbound defect fee on top of any placement fee already assessed. Sellers with shipments in transit targeting PBI3 or the South Florida region should verify their shipment plans and consider contacting Seller Support to confirm rerouting before the September 17 close date.

The PBI3 Closure: What Happens to Your Shipments on September 17

On September 17, 2026, Amazon permanently closes its PBI3 fulfillment center at 7600 LTC Parkway in Port St. Lucie, Florida. As Nova Data’s PBI3 closure analysis confirms, PBI3 anchored Amazon’s Southeast last-mile capacity into South Florida ZIP codes. After September 17, inventory targeting those ZIPs re-routes to nodes in Georgia (the ATL cluster) and Alabama (BHM6). The mechanical effect on sellers is threefold: a delivery promise slip for South Florida orders, a restructured inbound placement algorithm for Southeast-optimized shipment plans, and fresh volatility in placement fee calculations as Amazon recomputes default splits against the new node map.

How the placement fee changes when a node closes

Amazon’s placement fee algorithm assigns inventory to fulfillment centers based on demand concentration, network capacity, and delivery speed requirements. When a node closes, the algorithm redistributes the assignments that node was handling across the remaining network. For sellers whose products had high demand concentration in South Florida ZIP codes — consumer goods, perishables, fast-moving categories — the algorithm previously assigned PBI3 as a receiving location for shipments targeting that demand. After September 17, those assignments shift to ATL cluster nodes in Georgia and BHM6 in Alabama. The fee assessment for the new routing may differ from the fee that applied to PBI3 routing for the same inventory, because the distance and redistribution cost from the new receiving locations to the South Florida demand zone are different from the cost that PBI3’s proximity to that demand produced.

What this means for shipment plans created before September 17

Shipment plans created in Seller Central before September 17 that included PBI3 as a receiving location will be affected. Amazon has the ability to reroute in-transit shipments to alternative facilities, which it typically does when a facility closes. Sellers whose shipments are in transit to PBI3 around the close date should monitor the shipment status in Seller Central and expect receiving location changes. Shipments rerouted by Amazon to alternative facilities — rather than by seller choice — should not generate inbound defect fees for the routing change itself, but the practical timing around a facility closure creates ambiguity that sometimes produces incorrect fee assessments. Documenting the original shipment plan and the rerouting instruction is the evidence base needed to challenge any erroneous defect fee assessment connected to the closure.

If Your Revenue Is Florida-Heavy: What to Do Right Now

Sellers with significant Florida revenue concentration — particularly South Florida ZIP codes that PBI3 served — have 31 days to take specific actions before the closure affects their FBA economics.

Audit your current inventory by fulfillment center location

Go to Seller Central under Reports, then Fulfillment, then Inventory, then Inventory by Fulfillment Center. Download the current report and identify any inventory currently at PBI3. This inventory will be redistributed to other facilities after the closure — Amazon handles the redistribution internally, typically at no charge to sellers — but the redistribution affects the regional density of the seller’s inventory and therefore the Prime badge status for South Florida buyers. Inventory redistributed from PBI3 to ATL nodes is geographically farther from South Florida demand. The longer shipping distance from ATL to South Florida delivery addresses may push some orders from 1-day Prime to 2-day Prime delivery promise, which is the Prime badge change that affects conversion rate.

Adjust Q4 inbound shipment plans before September 17

Q4 inbound shipments in transit now — or being planned now — should be evaluated against the post-September 17 network. Shipment plans that relied on PBI3 as a receiving location for South Florida coverage should be updated to route inventory directly to the ATL cluster or BHM6 nodes that will serve that demand after closure. This routing change may affect the placement fee calculation for those shipments, because the fee is partly determined by which facility receives the inventory and the redistribution cost from that point. Running the updated shipment plan through Seller Central’s fee calculator before committing to the shipment allows comparison of the fee estimate under the pre-closure routing versus the fee estimate under the post-closure routing.

Prime Badge Instability After the Closure

Prime badge status on an ASIN is determined by Amazon’s assessment of whether it can deliver the product within the promised timeframe — typically 1-day or 2-day — to the buyer’s delivery address. When a fulfillment center that provided regional inventory coverage closes and inventory redistributes to a more distant node, Prime badge status can slip for buyers in the affected region.

The delivery slip mechanism

The mechanical effect of the PBI3 closure is a 1-day slip on delivery promise for a slice of Florida orders, tighter zone density on Prime badge decisions, and a bigger role for Amazon’s inbound placement fees when they recompute default splits. Sellers who lean on FBA for FL-heavy revenue will not see anything in their dashboards until Prime badge starts flickering on high-velocity SKUs — that is the wrong moment to notice. Prime badge flickering — where an ASIN shows Prime for some buyer locations but not others, or alternates between Prime and non-Prime at the same location — suppresses conversion rate for the affected orders without any visible account health violation or enforcement action. The seller’s listing looks correct in Seller Central while buyers in South Florida are seeing a degraded delivery promise that reduces their likelihood of purchasing.

The Q4 compounding problem

Prime badge instability during October, November, and December costs more than Prime badge instability at any other time of year, because peak season traffic amplifies the conversion impact of every percentage point of badge degradation. A South Florida buyer who sees a 3-day delivery promise on a Prime ASIN during BFCM is less likely to purchase than the same buyer seeing 1-day delivery — and that buyer’s behavior, multiplied across thousands of South Florida households shopping during peak, produces a measurable revenue reduction that does not appear as any specific Amazon enforcement event. It simply shows up as a conversion rate decline in the analytics for affected ASINs. Maintaining adequate inventory in the ATL cluster nodes before September 17, so that Atlanta-based inventory can cover South Florida demand at competitive delivery speeds, is the preventive action that preserves Prime badge stability through the closure transition.

The Q4 Intersection: Why the Timing Is Unusually Bad

The PBI3 closure on September 17 intersects with Q4 preparation in a way that amplifies every consequence described above. September 17 is 28 days before the October 15 peak fulfillment surcharge activation, and 34 days before the October 21 FBA minimal-split inbound cutoff for BFCM.

Inbound shipments in the closure window

Sellers sending Q4 inventory now — during the window that targets the October 21 and October 28 BFCM inbound cutoffs — are creating shipment plans that will be received both before and after the September 17 closure. A seller whose Q4 inventory ships in two ocean containers, one arriving September 10 and one arriving September 25, faces different placement fee calculations for each. The September 10 shipment is received under the pre-closure network — the September 25 shipment is received under the post-closure network, with PBI3 removed from the Southeast node map.

If the seller’s shipment plan was configured based on pre-closure placement fee estimates, the September 25 shipment’s actual fee may differ from what the plan showed. Verifying shipment plan fee estimates against the current Seller Central fee calculator — using post-September 17 routing assumptions — before committing to Q4 inbound volumes prevents this fee discrepancy from appearing as a surprise in October settlement reports.

The fee stack interaction

The placement fee changes from the PBI3 closure occur alongside the full Q4 fee stack: the $0.32 peak fulfillment surcharge active from October 15, the 3.5% fuel and logistics surcharge active since April, and the $2.40 per cubic foot peak storage rate from October 1. A seller who has modeled Q4 deal margins against the January 2026 rate card but not against the post-closure placement fee routing will be working from a fee estimate that understates the true cost of receiving inventory in the Southeast after September 17. See our Amazon Q4 2026 seller guide for the full Q4 fee stack framework that placement fee changes must be modeled against.

When Placement Fee Errors Arise From Network Rebalancing

Amazon’s placement fee system is automated, and network rebalancing events — facility closures, new facility openings, capacity reconfigurations — produce the conditions under which automated fee systems generate errors. The errors are not intentional, but they are real, and they require seller action to identify and recover.

The types of placement fee errors that arise during network changes

Fee charged at wrong size tier: Amazon’s system assigns size tiers during the inbound receiving process. Network transitions sometimes produce tier assignment errors where products are received and classified at a different size tier than their actual dimensions and weight support, resulting in a fee calculated at the wrong rate. Fee charged for optimized splits: sellers who selected Amazon-optimized splits — and therefore should pay zero placement fee — sometimes receive placement fee charges during network rebalancing because the system reassigns their shipment to a non-optimized routing as it adjusts to the new node map. Inbound defect fee for rerouting triggered by Amazon: shipments rerouted by Amazon’s system to avoid the closing PBI3 facility should not generate seller-facing inbound defect fees, but the automated system does not always correctly attribute routing changes initiated by Amazon versus routing errors caused by the seller.

How to identify placement fee errors

Download the FBA Inbound Performance report from Seller Central under Reports, then Fulfillment, then Inbound Performance. This report shows every inbound shipment, the placement option selected, the fee assessed, and any inbound defect fees. Cross-reference the fee assessed for each shipment against the rate card for the specific product’s size tier and shipping weight. Any placement fee assessed on shipments where Amazon-optimized splits were selected is an error — the optimized split option carries zero placement fee. For shipments rerouted by Amazon around the closure period, any inbound defect fee should be reviewed against the documentation of the rerouting instruction. When the documentation shows Amazon initiated the rerouting, the defect fee is an erroneous assessment that qualifies for a reimbursement claim.

Filing a placement fee reimbursement claim

Placement fee and inbound defect fee errors submit through Seller Central under Help, then Contact Us, then FBA Issue, then Fee Dispute. The claim must identify the specific shipment ID, the fee type assessed, the fee amount charged, and the specific basis for disputing the assessment — incorrect size tier, zero-fee option selected, or Amazon-initiated rerouting. Amazon’s fee dispute team reviews the claim against its receiving records. Denied claims escalate through the standard case escalation path. When Amazon denies reimbursement for fee errors that the receiving records clearly support, legal escalation through formal FBA billing dispute procedures and, when the amount justifies it, pre-arbitration demand letters to Amazon’s legal counsel is the next step. See our Amazon FBA reimbursement guide for the complete claim framework.

FBA Inventory Claims Connected to the PBI3 Closure

Beyond placement fee errors, the PBI3 closure creates two specific FBA inventory claim scenarios that sellers should anticipate.

Inventory lost or damaged during the facility transition

When a fulfillment center closes, Amazon redistributes its inventory to other facilities. The redistribution process involves physical movement of inventory — picking, packing, and shipping units from PBI3 to ATL and BHM6 nodes. Physical inventory movement creates opportunities for units to be lost, miscounted, or damaged during the transition. Amazon’s standard FBA reimbursement policy covers inventory that is confirmed lost or damaged while in Amazon’s possession — the PBI3-to-ATL redistribution is a movement within Amazon’s possession, and any units lost or damaged during it are reimbursable. Monitoring the FBA Inventory Reconciliation report in Seller Central after September 17, comparing unit counts before and after the redistribution, and filing reimbursement claims for any units that disappear during the transition without a corresponding customer sale is the claim process for this scenario.

Receiving delays affecting BFCM eligibility

Sellers whose Q4 inbound shipments are received and processed at PBI3 around the closure date may experience receiving delays as the facility winds down operations. A shipment received but not processed into inventory before the facility closes on September 17 may need to be transferred to another facility for completion, adding days to the receiving timeline. For shipments targeting the BFCM deal events, receiving delays that push inventory past the deal eligibility cutoff — the point at which inventory must be in FBA to count as available for a deal submission — can cause deal deactivations even when the inventory was timely shipped and delivered. Documenting the delivery date and time relative to the deal eligibility cutoff, and preserving the carrier delivery confirmation, is the evidence base for challenging deal deactivations that resulted from Amazon-side receiving delays rather than seller-side timing failures.

How to Minimize Placement Fees on Q4 Inbound Shipments

The post-closure fee landscape and the Q4 fee stack together make minimizing placement fees on Q4 inventory more financially important than at any previous point in the program’s history. Three strategies reduce or eliminate placement fees on the Q4 inbound volume.

Strategy 1: Amazon-optimized splits for high-volume SKUs

By selecting Amazon-optimized shipment splits — sending inventory to four or more Amazon-designated fulfillment centers — sellers pay zero inbound placement fees. The tradeoff is higher freight complexity and cost on the inbound side, which a freight forwarder or 3PL managing the multi-destination distribution can often handle for less than the placement fee the single-destination option would have charged, as Adverio’s placement fee analysis documents with specific case examples. For high-volume Q4 SKUs where the placement fee at minimal splits would total thousands of dollars, the comparison between the placement fee and the incremental freight cost of splitting to four destinations frequently favors the split. Running the math before each Q4 shipment using the current Seller Central fee calculator produces the data needed for this decision on a per-shipment basis rather than relying on a general rule.

Strategy 2: Amazon Warehousing and Distribution for buffer stock

AWD’s automatic replenishment to FBA eliminates the inbound placement fee for inventory flowing through AWD into FBA. Inventory sent to AWD is subject to AWD storage fees rather than FBA inbound placement fees, and AWD’s auto-replenishment handles the FBA distribution automatically. For Q4 inventory buffer stock — units beyond the base BFCM quantity that serve as safety stock against velocity surprises — AWD is a fee-efficient alternative to sending excess inventory directly to FBA at full placement fee rates. The BFCM inbound cutoff for AWD shipments is October 14, one week earlier than the minimal-split FBA cutoff. See our Amazon FBA New Selection Program guide for the FBA fee reduction programs available alongside AWD for eligible products.

Strategy 3: Packaging optimization for size tier reduction

Placement fees are calculated based on size tier, and reducing a product’s size tier through packaging optimization reduces the per-unit fee. A product that falls just above the small standard upper weight limit into large standard pays a materially higher placement fee per unit. Packaging redesign that brings the product’s dimensions and weight into the small standard tier — without compromising product protection — produces a permanent per-unit placement fee reduction that compounds across every future shipment. For Q4 volumes specifically, a tier reduction achieved before the first Q4 inbound shipment applies to every unit shipped during the peak season.

Frequently Asked Questions About FBA Inbound Placement Fees and the PBI3 Closure

Will Amazon notify me if my shipment gets rerouted away from PBI3?

Amazon updates shipment status in Seller Central as shipments are received and processed. A shipment that was planned for PBI3 but rerouted will show the updated receiving location in the Manage FBA Shipments view. Amazon does not always send proactive email notification of receiving location changes — checking the shipment status directly in Seller Central around the September 17 close date is the reliable monitoring method. Setting up Seller Central notification preferences for FBA shipment status changes ensures alerts arrive when status updates occur.

I selected Amazon-optimized splits but was still charged a placement fee. What do I do?

Optimized splits carry zero placement fee. A placement fee charge on a shipment where optimized splits were selected is a billing error. Pull the shipment plan from Seller Central to confirm the placement option selected, screenshot the confirmation showing optimized splits, and file a fee dispute through Seller Central identifying the shipment ID, the option selected, and the fee incorrectly charged. The dispute should result in a credit for the incorrectly charged amount. If the fee dispute is denied despite clear documentation that optimized splits were selected, escalate through the case management system and, if necessary, through the FBA billing dispute escalation path.

My Prime badge is showing inconsistently after September 17. Is this connected to PBI3?

Yes, potentially. Prime badge instability for South Florida delivery addresses after September 17 is the expected consequence of PBI3 inventory redistributing to ATL and BHM6 nodes that are geographically farther from those delivery addresses. The inconsistency resolves as Amazon’s placement algorithm adjusts and as sellers position adequate inventory at the new nodes serving South Florida demand. Monitoring Prime badge status by location — Amazon’s Delivery Promise report shows delivery promise times by geography — allows sellers to identify which delivery ZIPs are affected and to adjust inventory positioning accordingly. Sellers who cannot restore Prime badge coverage for affected ZIPs through inventory repositioning should evaluate whether the revenue impact in those ZIPs justifies a direct FBA shipment to an ATL or BHM6 node with the optimized split option.

Does the PBI3 closure affect FBM sellers?

The PBI3 closure directly affects FBA inventory and placement fees. FBM sellers who fulfill their own orders are not affected by PBI3’s closure because their inventory is not stored at Amazon’s fulfillment centers. However, FBM sellers in the South Florida region may experience carrier capacity effects if Amazon’s post-closure logistics restructuring in the Southeast creates temporary carrier capacity shifts — PBI3’s 494-person workforce and its associated carrier relationships represented significant regional logistics activity. FBM sellers in South Florida should monitor carrier performance and On-Time Delivery Rate metrics after September 17 for signs of regional carrier capacity constraints that could affect their OTDR compliance. See our Amazon business hour delivery rate guide for the OTDR enforcement framework relevant to FBM sellers in this region.

How DAM Law Firm Can Help

DAM Law Firm handles FBA fee disputes and inventory claim escalations when Amazon’s standard reimbursement and dispute processes have not produced resolution — including the specific placement fee error and inventory loss scenarios that fulfillment center closures like the PBI3 shutdown create.

Placement fee and inbound defect fee dispute escalation

When placement fee errors from the PBI3 closure — incorrect size tier assessments, optimized-split fees charged in error, inbound defect fees for Amazon-initiated rerouting — have been denied through the standard fee dispute process without adequate factual basis, we escalate through the formal FBA billing dispute process and, when the amount justifies it, through pre-arbitration demand letters to Amazon’s legal counsel. Amazon is obligated under the BSA to charge fees in accordance with its published fee schedule. Fee charges that do not conform to the published schedule are BSA breaches that create enforceable legal claims. See our pre-arbitration demand letter guide for the legal escalation framework.

FBA inventory reimbursement claims for closure-related losses

Inventory lost or damaged during the PBI3-to-ATL redistribution that Amazon does not voluntarily reimburse through the standard FBA reconciliation process is eligible for formal reimbursement claims through the FBA dispute path. Our Amazon withheld funds team handles fee and inventory recovery situations where Amazon’s standard resolution process has not produced reimbursement, and our arbitration against Amazon team handles escalation to AAA arbitration for significant unreimbursed inventory and fee claims when internal processes are exhausted.

Account health and listing issues connected to the closure

When Prime badge instability from the PBI3 closure produces account health effects — conversion rate drops that affect BSR and trigger algorithmic enforcement, or OTDR violations connected to post-closure delivery promise changes — our Amazon account suspensions team and our Amazon listing suspensions team handle enforcement response and appeal when standard account health remediation has not resolved the issue. Contact our team for a same-day assessment if the PBI3 closure is producing fee, inventory, or account issues that Seller Central support has not addressed.

Related DAM Law Firm services:

• Amazon Withheld Funds — fee and inventory recovery for placement fee errors and closure-related inventory losses Amazon has not voluntarily reimbursed
• Arbitration Against Amazon — AAA arbitration for significant unreimbursed fee and inventory claims when internal dispute processes are exhausted
• Amazon Account Suspensions — account enforcement response when Prime badge instability or delivery metric violations connected to the closure produce account-level consequences
• Amazon Listing Suspensions — listing reinstatement when closure-related delivery changes produce listing-level enforcement actions
• Amazon Product Compliance Lawyer — proactive compliance review for sellers restructuring inbound logistics around the post-closure Southeast network

This article is for general informational purposes only and does not constitute legal advice. Fee amounts and network configurations are subject to change. Verify all fee rates in Seller Central before making business decisions. Contact DAM Law Firm for legal advice tailored to your situation.

Related articles from DAM Law Firm

• Amazon Q4 2026: The Complete Seller Guide to Deadlines, Fee Stack, and Enforcement Risk
• Amazon FBA Peak Season Surcharge 2026: What It Costs and What to Do Before October 15
• Amazon FBA Inventory Reimbursement 2026: How to Recover Money Amazon Owes You
• Amazon FBA Aged Inventory Surcharge 2026: How to Avoid It and When to Remove
• Amazon Pre-Arbitration Demand Letter: What It Is, When to Send One, and What It Should Say