Side Letters in SPVs: MFN and When They Appear

A side letter is a bilateral agreement between the vehicle (or GP) and one investor that grants rights or economics the operating agreement does not give every member. In SPVs they appear when a lead LP, strategic angel, or institution will not close on template terms alone. Most-favored-nation (MFN) clauses then decide whether those special terms must be offered to others. That is the risk that turns one quiet concession into a portfolio of matching obligations.

This is general information, not legal advice. Counsel drafts and conflicts side letters against the OA and any LPA. Confirm live prices on Allocations fees. For a broader primer, see Side letters in SPVs: what you need to know. This page focuses on when side letters show up in deal SPVs versus funds, and how MFN risk spreads.

When side letters appear in deal SPVs

Single-asset SPVs are often short-form: one close, one asset, a small member list, a promote in the OA. Side letters still appear when:

• A large check asks for fee or promote relief the teaser never showed.

• An institution needs transfer, ERISA, or reporting language the template OA omits.

• A co-investor demands information rights or consent on follow-on sales.

• A founder-led syndicate promises a strategic LP extra update rights that other angels do not get.

Because the investor count is small, one side letter can represent a large share of committed capital. That makes MFN especially sharp: if you grant MFN to two LPs and then give a third a better fee cut, you may owe the first two the same cut.

Funds use side letters more often and with thicker MFN schedules. The mechanics are the same; the volume is higher. Emerging managers who graduate from SPVs to a Fund inherit that volume — plan the MFN matrix before first close, not after LP four asks. See when emerging managers should raise a fund.

What usually lives in an SPV side letter

Common categories (illustrative, not exhaustive):

Side letters do not replace the OA. They sit beside it. If the OA says one promote and the side letter says another for one member, counsel must reconcile which document controls for that member — and whether MFN forces a rewrite for everyone else.

Document hierarchy matters. See PPM vs subscription agreement vs operating agreement for how offering docs stack. The side letter is another layer, not a substitute PPM.

MFN: the clause that multiplies one concession

An MFN clause generally lets an LP elect terms that are more favorable than those granted to other LPs in side letters (or sometimes in the OA). Scope varies:

• All terms vs economics only. Broad MFN can pull information rights and consents, not only fee cuts.

• Time window. Some MFNs cover side letters signed through final close; some run longer.

• Carve-outs. Strategic LPs, affiliated LPs, seed LPs, or regulatory-driven terms are often carved out — if you write the carve-outs.

• Election mechanics. Does the LP auto-receive better terms, or must they elect within a stated number of days of disclosure?

Without a side-letter register, GPs forget who has MFN and grant a "one-off" that is not one-off. Build a register before first close: LP name, date, key grants, MFN yes/no, carve-outs.

Disclosure timing matters. If MFN LPs must see other side letters to elect, you need a redaction and delivery process that matches the OA confidentiality rules. Do not email unredacted side letters to the whole cap table from a personal inbox.

SPV vs fund: same tool, different blast radius

Allocations' live fees page (fetched 7 Sep 2026) lists side letters included on Standard SPV ($9,950), Premium SPV ($19,500), and Fund ($19,500/year). Platform carry is 0%. "Included" means administration can process agreed side letters within the SKU; it does not invent economics, waive MFN, or replace counsel. Additional fees may apply for extras outside the published matrix — confirm on /fees. See also Allocations pricing explained.

For carry vs platform claims, see Platform carry vs GP carry. For fund fee context, see Management fee in VC and PE funds.

Operational rules that keep MFN from becoming a surprise

1. No soft-circle side terms. If it is not in a draft side letter or OA, it is not a close condition.

2. One register. Every executed side letter lands in the same index the admin and counsel share.

3. MFN election calendar. After each close (or after each new side letter), run the disclosure/election process the documents require.

4. Conflict check against OA. A side letter that contradicts a locked OA section needs an amendment path, not a silent override.

5. Capital call and distribution systems. Fee cuts and promote changes must flow into call notices and waterfall worksheets. See SPV capital calls for notice hygiene.

Do not promise returns in a side letter. Economics clauses change fee or promote splits; they are not performance guarantees. Antifraud rules still apply (SEC, Private Funds, fetched 7 Sep 2026).

Side letters and capital calls

If a side letter cuts fees or changes who pays organizational expenses, the next capital call notice must reflect the economics for that LP. A notice that calls everyone at the same gross rate while a side letter promised a fee holiday creates an immediate reconciliation dispute. Update the call schedule in the admin system when the side letter is executed — not after the wire is late. The capital-call field list (amount, due date, wires, authority) still applies; the amount column simply differs by LP where the documents say so.

Should you agree?

Agree when the LP's ask is narrow, carved from MFN where appropriate, and operable in your admin system. Decline or narrow when the ask rewrites control rights for one member in a way that breaks the OA, or when broad MFN would force you to give the same deal to everyone at a price the vehicle cannot support as a cash expense or promote cut.

A side letter is a precision tool. MFN decides whether that precision stays local or becomes the new template.

What is an SPV side letter?

A bilateral agreement giving one investor rights or economics beyond the standard operating agreement. It sits beside the OA; it does not replace it.

What is an MFN clause in a side letter?

Most-favored-nation language that lets an LP claim more favorable terms granted to other LPs, usually via other side letters, subject to the clause's scope, timing, and carve-outs.

Do Allocations SPVs include side letters?

Yes — the live fees page lists side letters included on Standard SPV ($9,950), Premium SPV ($19,500), and Fund ($19,500/year) as of 7 Sep 2026. Platform carry is 0%. Inclusion is administration capacity, not automatic special economics for every LP.

Are side letters more common in funds than SPVs?

Often yes, because funds have more LPs and longer lives. Deal SPVs still use them for large or institutional checks. MFN risk exists in both.

Can a side letter promise investment returns?

No. Side letters may change fees, promote, or rights. They should not promise performance. This page is educational, not investment advice.