Every private fund has a public set of terms and a private set of agreements running underneath them. The side letter is where the real negotiation lives, and the distance between what a first-close LP receives and what a late, smaller LP receives can be structurally significant, regardless of what the fund documents say about equal treatment.

How the Stratification Works

Side letters are bilateral agreements between a GP and a specific LP, negotiated outside the Limited Partnership Agreement. They grant rights the LPA does not: reduced management fees, carried interest carve-outs, co-investment rights with reduced or zero carry, enhanced information packages, excuse rights from specific investments, and key-person triggered redemption options. A large sovereign wealth fund or pension anchor LP entering at first close typically negotiates a package covering most of these categories. A family office entering the same fund at second close on standard terms receives none of them by default.

The practical effect is a two-class fund structure operating under a single legal wrapper. Both LPs hold units with identical economic exposure to the underlying portfolio. Their governance rights, fee loads, and information access diverge considerably.

What MFN Actually Provides

Most Favored Nation clauses are the mechanism offered to smaller or mid-tier LPs as a nominal equalizer. An MFN provision entitles the LP to elect into any more favorable terms subsequently granted to another LP in the same fund, provided those terms are comparable in kind. The operative phrase is “comparable in kind.” GPs routinely structure anchor LP rights as compensation for commitments above a defined threshold, making those rights technically ineligible for MFN election by smaller LPs who did not meet the threshold. The MFN clause holds; the economics of the clause are hollowed out by the threshold architecture surrounding it.

A standard MFN notice period runs 30 to 60 days post-close, requiring the LP to affirmatively elect into available terms. LPs that do not have internal processes to review side letter disclosures within that window forfeit the option. The right exists; it goes unexercised.

The Information Asymmetry Underneath

Most LPAs include confidentiality provisions preventing LPs from disclosing the terms of their own side letters to co-investors. The GP, by contrast, holds visibility across all bilateral agreements. This creates a structural information asymmetry: the GP knows the full distribution of LP rights; each LP knows only its own. Secondary market buyers and fund-of-funds investors frequently underwrite this risk without sufficient data, since side letter obligations typically transfer with the interest but are not always fully disclosed in secondary transactions.

• Co-investment rights granted via side letter do not automatically bind a successor GP after a key-person event unless explicitly drafted to survive.
• Excuse rights, if exercised, can alter a fund’s capital call sequencing and affect unfunded commitment ratios for other LPs.
• Enhanced reporting rights negotiated by one LP may not trigger disclosure obligations to the broader LP base under ILPA guidelines unless the fund has adopted them by reference.

The Operator Read

For LPs evaluating a fund commitment, the side letter negotiation is not a post-subscription formality. It is where the actual terms of participation are set. The LPA establishes the floor; the side letter determines where a given LP actually sits relative to that floor and relative to every other LP in the vehicle. Capital allocators who treat side letter review as legal overhead rather than commercial negotiation are effectively accepting a subordinate position in a hierarchy they may not fully see. The structural setup rewards those who enter the conversation early, negotiate specifically, and understand what MFN thresholds actually permit them to elect into before signing.