Resale Price Method (RPM): When It Fits and When It Fails

The resale price method (RPM) works in reverse from every other OECD method. Instead of starting at the controlled price and asking “is it right?”, it starts at the reseller’s resale price to unrelated customers and walks backwards: subtract the gross margin that comparable independent resellers earn, and what remains is the arm’s length purchase price for the controlled transaction.

It is the mirror image of CUP: CUP takes an independent price and applies it to the controlled transaction; RPM takes an independent margin and applies it to the controlled transaction’s downstream price.

How RPM works

Arm's length purchase price = resale price × (1 − comparable gross margin %)
Gross margin %              = (resale price − purchase cost) ÷ resale price

The comparable gross margin comes from independent resellers of the same product or service, reselling under comparable circumstances — same market, similar functions, similar risks. The tested party under RPM is the reseller on the controlled purchase, and the method only holds if the reseller adds no significant value between purchase and resale.

When RPM is the right method

RPM fits a narrow, well-understood fact pattern — the limited-risk reseller/distributor:

Condition	Why it matters
No manufacturing or significant processing	Any production step moves the case to Cost Plus
Minimal inventory risk	Inventory held is working capital, not a value driver
No significant marketing intangibles	No brand or customer relationships owned by the reseller
No R&D, no product development	Value is not created after purchase
Routine credit terms, standard contracts	The margin is a function of the market, not the contract

If the reseller owns the brand, does product adaptation, or carries meaningful inventory or credit risk, the reseller’s margin is no longer “routine” and the RPM’s premise — that the resale price minus a routine margin prices the controlled purchase — collapses.

RPM and the Gross Margin Method

In Indian practice the same arithmetic appears as the Gross Margin Method (GMM): the gross margin of comparable uncontrolled resellers is used directly as the profitability standard under the methods listed in Rule 10B. Where RPM is invoked in a US or OECD-style file, GMM is often what the same analysis becomes in an Indian file — the denominator and comparables are identical; only the label and the rule number change. See the Gross Margin Method guide for the denominator discipline that both share.

Worked example: pharmaceutical distributor

An Indian distributor purchases an API from its overseas affiliate and resells it to unrelated formulators. FY 2025-26:

Item	Amount
Resale price to unrelated customers	₹120 per kg
Purchase price from affiliate (as billed)	₹95 per kg
Gross margin as booked	20.8%

Five independent Indian resellers of the same API grade, reselling to the same customer base, report gross margins of 16%, 17.5%, 18%, 18.5% and 19.5%. The interquartile range is 17.5% to 18.5%; the median is 18%.

Arm's length purchase price = 120 × (1 − 0.18) = ₹98.40 per kg

The billed price of ₹95/kg implies the distributor earned more than the comparable pool — the affiliate is under-remunerated. The arm’s length purchase price is ₹98.40, and the file must either support the ₹3.40/kg difference with a quantified comparability factor (the distributor carries longer credit, bargained freight) or move the price to the comparable level.

Where RPM fails

• The reseller adds value. Any manufacturing, formulation, branding or customer-management function means the reseller’s margin is not the market’s routine reseller margin. Fall back to TNMM on the reseller or Profit Split.
• No comparable resellers exist. A unique product with no independent reseller pool makes the method unusable — the “comparable gross margin” has no source.
• Multi-product distributors. RPM needs a product-level resale price and a product-level margin. A distributor with a blended portfolio either must be split by product (data-heavy) or moved to a net PLI under TNMM.
• Different risk profiles. If the controlled reseller carries inventory risk or credit terms that the comparables do not, the margin gap is real and unexplained — RPM will show a difference the file cannot justify.
• Resale price is not clean. Resales to related parties, bundled pricing with services, or discounts that do not exist in the independent channel contaminate the starting number.

Questions the TPO asks

Expect these if RPM is the declared method:

1. Why RPM rather than TNMM — what makes the reseller’s margin routine?
2. Source of the comparable gross margins: which companies, which years, which market, and why are their functions comparable?
3. Who bears inventory risk, credit risk and price risk — show the contracts.
4. Does the reseller own any trademark, customer list or regulatory registration? If yes, RPM’s premise is gone.
5. Show the gross margin by product, not blended across the portfolio.

Choosing between CUP, RPM and TNMM

	CUP	RPM	TNMM
Compares	a price	a margin on the resale price	a net PLI of the tested party
Needs	an identical uncontrolled transaction	independent resellers of the product	a comparable company pool
Fits	commodity goods, internal CUP	limited-risk resellers	services, most Indian fact patterns
Fails when	nothing is “identical”	the reseller adds value	the pool is weak or the PLI is wrong

The decision runs through the best method rule: the method that gives the most reliable, least-adjustment-dependent measure of arm’s length pricing wins. For most Indian distribution and service transactions that is TNMM — RPM earns its place where a clean reseller pool exists and the fact pattern is genuinely limited-risk. See the methods overview for the full decision tree.