Partnership by Accident: What New York's Default Rules Do to You Without an Operating Agreement

Founders describe it the same way almost every time: "We haven't set up the legal stuff yet." Meaning no LLC, no lawyer, nothing signed. Just two people building something and splitting what comes in.

New York disagrees with the premise. If that describes you, the legal stuff is already set up. You have a general partnership, formed the moment you started carrying on a business together for profit, and it came with a complete set of terms drafted by the state legislature. You have simply never read them.

How You Formed a Partnership Without Noticing

Partnership Law § 10 defines a partnership as an association of two or more persons carrying on a business as co-owners for profit. That is the entire test. No filing, no written agreement, no handshake, and no intent to "form a partnership" is required; courts look at what you are doing, not what you meant. And under § 11, sharing the profits of a business is prima facie evidence that you are partners. Splitting the Venmo from your first paid workshop may have done more legal work than you realized.

The Terms You Never Negotiated

Here is the deal the default rules gave you:

• Equal split, regardless of who put in what. Absent an agreement, partners share profits equally (Partnership Law § 40). The partner who contributed 90% of the capital and the partner who contributed a laptop share the upside the same way. Whatever informal understanding you had lives in two memories, and default rules beat foggy memories.
• Equal say, and either of you can act alone. Partners have equal management rights (§ 40), and every partner is an agent of the partnership whose acts in the ordinary course bind the firm (§ 20). Your partner can sign a contract you have never seen, and it is your contract too.
• Personal, unlimited liability, including for each other. Partners are liable for the partnership's obligations: jointly for its debts and contracts, and jointly and severally for a partner's wrongful acts (Partnership Law §§ 24 through 26). There is no shield, and there is no ceiling. Your partner's business mistake can reach your personal assets.
• No pay for the work. A partner is not entitled to compensation for services to the partnership (§ 40); the default assumes the profit split is the pay. The founder working sixty-hour weeks and the founder who drifted away earn the same share.
• Fiduciary duties you never scoped. Partners owe each other the highest duties of loyalty and good faith (§ 43). The standard comes from New York's most famous sentence about business partners: co-adventurers owe "the punctilio of an honor the most sensitive" (Meinhard v. Salmon, 249 N.Y. 458 (1928)). A noble standard, and a litigation magnet when nobody defined what was inside and outside the venture.
• Terminable at will, by either of you, at any time. A partnership with no agreed term can be dissolved by the express will of any partner (§ 62). Your business is subject to a unilateral off-switch held by the other person. In any serious disagreement, that is not a technicality; it is negotiating leverage.

Why "But We Trust Each Other" Doesn't Answer This

Trust is necessary and beside the point. Personal liability runs to third parties (the vendor, the landlord, the injured customer), and no amount of trust between partners controls what a stranger does. The dissolution-at-will rule shapes leverage even between people who never use it; both of you know it is there. And the equal-split default overrides your informal deal precisely in the situation where it matters, which is when your memories of the deal no longer match. Default rules are not for the good days. They are the terms that govern the bad ones, and New York's were not written with your business in mind.

One housekeeping note while we are here: an unregistered partnership operating under a trade name also owes a certificate of assumed name filing in each county where it does business (General Business Law § 130), and cannot maintain a lawsuit on its contracts until it files. Even the accidental structure has compliance obligations.

The Fix Is the Document, Not Just the Filing

The repair is two moves, not one. Forming an LLC (in New York: $200 in articles, plus the publication requirement covered elsewhere in this series) gets you the liability shield and ends the accidental partnership. But the filing alone just swaps one set of defaults for another. The document that actually replaces the legislature's terms with yours is the operating agreement: the split (and whether it should even be equal; see this series' memo on founder equity), who decides what, tie-breakers for a 50/50 company, what happens when someone leaves (vesting), and how someone exits on purpose. New York is direct about this: LLC Law § 417 says members "shall" adopt a written operating agreement. There is no penalty for ignoring that command. The penalty is living under default rules, which is exactly the situation you are in right now.

Conclusion

You do not get to choose whether your business has a legal structure; you only get to choose which one, and whether its terms were written by the two of you or by Albany in 1919. If you recognized your business anywhere in this memo, the fix costs a filing fee and a set of documents. The current arrangement costs nothing today and compounds quietly: every contract signed, every dollar shared, every week of unlimited mutual liability. An operating agreement, at bottom, is you overruling the legislature. Overrule it early.

VMG Business Advisory converts accidental partnerships into properly structured New York LLCs: formation, publication, and operating agreements that replace the defaults with terms the founders actually chose.

Related practice areas: Startup Advisory · Corporate Governance

This article is provided for general informational and educational purposes only. It does not constitute legal advice or create an attorney-client relationship. The information is current as of September 2026 and subject to change. Whether a partnership exists, and the consequences if one does, depend on specific facts; consult qualified counsel about your situation. Attorney Advertising.