Every fund that closes institutional capital will have side letters. This is not optional — it is the market reality. Institutional investors have their own legal and compliance requirements that the standard limited partnership agreement does not address, and large-check investors have the negotiating leverage to extract economic concessions that the LPA does not provide. A manager who treats side letters as a nuisance rather than a substantive legal process is going to create commitments they do not understand, obligations that conflict with each other, and MFN exposure they did not anticipate.

A side letter is a bilateral agreement between the general partner and a specific limited partner that modifies, supplements, or creates rights and obligations outside the LPA. It does not amend the LPA itself — other LPs are not parties to it, and the LPA remains the governing document for the fund as a whole. But the side letter controls as between the GP and that particular LP, and its terms can have fund-wide implications through the MFN mechanism.

Why Side Letters Exist

Side letters serve two distinct functions. The first is regulatory and compliance accommodation. A public pension fund investing under ERISA, a sovereign wealth fund with disclosure restrictions, a state pension fund subject to FOIA, or a European LP with ESG policy requirements cannot simply sign the standard LPA and be done. They need contractual protections that address their specific legal constraints — protections that are meaningless to other LPs and therefore do not belong in the fund's governing document. The GP has every incentive to grant these protections: they cost nothing and close the check.

The second function is economic. Large anchor investors use their commitment size as leverage to negotiate fee discounts, carry reductions, and co-investment rights. A $50 million commitment to a $300 million fund is 17% of the fund — that LP has real leverage and will use it. Economic concessions granted in side letters have direct cost to the manager and, through the MFN mechanism, potential cost to the manager across the LP base.

The MFN Clause

The most consequential side letter provision — the one that every manager must understand before granting any concession to any LP — is the most favored nation (MFN) clause. An MFN clause gives the LP the right to receive any more favorable terms granted to any subsequent LP in the same fund, to the extent the subsequent terms are more favorable than what the original LP received. In practice, MFN clauses operate as follows: after each subsequent closing, the GP sends each MFN LP a notice listing the new terms granted to new LPs; each MFN LP then has an election period (typically 30 to 60 days) to elect to receive any of those terms in lieu of or in addition to its existing side letter terms.

The scope and carve-outs of the MFN clause determine how much risk it creates. A broad MFN with no carve-outs means that every economic concession granted to any LP — including anchor discounts granted at the first close, regulatory accommodations that only apply to specific investor types, and size-based fee reductions — is potentially available to every MFN LP in the fund. That is almost never what the GP intends. Standard MFN carve-outs include:

  • Size-based accommodations (fee discounts granted to an LP committing $50M+ are not available to an LP committing $5M)
  • Regulatory-specific accommodations (ERISA provisions are not available to non-ERISA investors; sovereign wealth fund terms are not available to family offices)
  • First-close or anchor investor terms negotiated as part of a specific fundraising arrangement
  • Terms that were required as a condition of a particular LP's legal or fiduciary obligation, not negotiated as an economic concession

GPs should resist broad MFN clauses with minimal carve-outs. The practical result is that any concession granted anywhere in the fund potentially becomes a concession granted everywhere, and the GP loses the ability to use economic terms as a fundraising tool for subsequent closes.

Economic Terms: Fees, Carry, and Co-Investment

Anchor investors — typically the first LP or LPs to commit, often at a first close that gives the fund credibility for subsequent fundraising — routinely negotiate management fee discounts. A discount of 25 to 50 basis points on the management fee is common for commitments above a certain size threshold. Some anchors negotiate a blended rate (e.g., 1.5% on the first $25M, 1.0% on amounts above $25M). Carry reductions for very large commitments — 17.5% instead of 20%, for example — are less common but not unheard of in a competitive fundraising environment.

Co-investment rights are among the most valuable side letter concessions and among the most operationally complex. A co-investment right gives the LP the right to participate in individual fund investments alongside the fund, typically with no management fee and no carried interest on the co-invest portion. From the LP's perspective, this is pure alpha — exposure to the GP's best ideas without the drag of fund economics. From the GP's perspective, co-investment rights create obligations to offer deal flow to certain LPs before others, and the operational burden of managing co-investment vehicles alongside every significant fund investment can be substantial. GPs should draft co-investment provisions carefully: distinguish between a right of first offer (the LP gets to see the opportunity before it is filled) versus a contractual obligation to allocate a specific percentage; specify that co-investment is subject to the GP's discretion based on deal size, timing, and regulatory considerations; and make clear that co-investments do not count toward the LP's fund commitment for purposes of management fee calculations.

Regulatory and Compliance Terms

ERISA investors. If the fund accepts capital from ERISA benefit plan investors — pension plans, 401(k)s, certain IRAs — and plan asset investors aggregate to 25% or more of any class of equity interests, the fund's assets become "plan assets" under ERISA, which subjects the GP to ERISA fiduciary obligations and the prohibited transaction rules. Most funds avoid this outcome by keeping ERISA investors below the 25% threshold or by qualifying as a "venture capital operating company" (VCOC) or "real estate operating company" (REOC). ERISA investors typically require side letter representations confirming that the fund does not and will not hold plan assets, or — if the fund is structured to accommodate plan asset status — confirming compliance with applicable ERISA requirements.

Sovereign wealth funds. Sovereign wealth funds frequently have restrictions on investments that create U.S. tax filing obligations (ECI issues), restrictions on investments in specific sectors (defense, certain natural resources), and requirements for representations regarding the GP's compliance with anti-bribery and anti-corruption laws. Some sovereign wealth funds require periodic reporting on the fund's compliance with their own responsible investment policies.

Public pension funds and FOIA. Many U.S. state pension funds are subject to their state's freedom of information laws, which can require disclosure of investment records — including fund financial statements and capital account information — in response to public records requests. These LPs need contractual assurances that the GP will treat certain fund information as confidential and will promptly notify the LP if a FOIA request is received so the LP can seek a protective order or invoke applicable exemptions. GPs should understand that this does not mean they can refuse to cooperate with valid legal process; it means the LP needs a process right, not an absolute exemption.

Information Rights

Institutional LPs require more information than the standard LPA provides, and they require it on a defined schedule. Standard enhanced information rights provisions include: quarterly financial statements (unaudited) within 45 to 60 days after each quarter end; annual audited financial statements within 120 days after fiscal year end; annual Schedule K-1s within a specified period after year end; capital account statements with each quarterly report; access to the GP and investment team on an annual basis for a portfolio review meeting; and access to the GP's books and records relating to the LP's investment (subject to reasonable confidentiality restrictions).

Some larger institutional LPs negotiate for portfolio company-level financial information — quarterly financials from the underlying investments. Most GPs resist this because it requires portfolio company consent (which may not be obtainable) and creates diligence obligations the GP has not committed to in the LPA. A middle ground is providing portfolio company information on a confidential basis to the extent the GP has discretion to share it without violating confidentiality agreements with the companies.

ESG and Responsible Investment Provisions

ESG side letter provisions have become standard from European institutional investors and increasingly common from U.S. public pension funds and endowments. These provisions vary significantly in scope and obligation. The lightest version requires the GP to represent that it has considered ESG factors in its investment process — a representation most GPs can make without changing anything they are already doing. More demanding versions require the GP to provide periodic ESG reporting, apply specific exclusion screens (no investments in tobacco, weapons, private prisons), or commit to a particular ESG framework (UN PRI, TCFD). The most demanding provisions require the GP to obtain ESG representations from portfolio companies and report on their compliance.

GPs should be precise about what they are committing to. A representation that the GP "considers" ESG factors is very different from a covenant that the GP will "not invest in" specific sectors. The former is almost always defensible; the latter creates a contractual constraint that must be tracked against every investment.

Managing a Growing Side Letter Population

As the fund scales and the LP count grows, side letter obligations can become a significant compliance burden. A fund with 20 institutional LPs may have 20 separate side letters, each containing slightly different versions of MFN clauses, information rights timelines, and reporting obligations. If these are not systematically tracked, the GP will miss obligations, provide inconsistent information to different LPs, and create MFN conflicts it does not detect until an LP raises them.

The practical solution is a side letter matrix — a structured summary of every obligation in every side letter, organized by provision type — that is maintained and updated as new LPs are admitted. This matrix also serves as the tool for managing MFN elections: when a new LP receives terms at a subsequent close, the matrix allows the GP to quickly identify which existing MFN LPs may be entitled to elect those terms and what the cost of that election would be. Side letter management is not a documentation exercise — it is a risk management function.