Can a US shareholder agreement bind the company itself?

In Delaware it can, since the addition of 8 Del. C. § 122(18). Notwithstanding the board's management authority, the corporation may contract with current or prospective stockholders in that capacity, restricting itself from specified actions, requiring named persons or bodies to approve before it acts, or covenanting that specified actions will or will not be taken. Any provision contrary to the certificate of incorporation, or that would be contrary to Delaware law if in the certificate, is unenforceable against the corporation.

How does New York treat shareholder control of the board?

Restrictively. New York Business Corporation Law § 620(b) makes a provision that improperly restricts the board, or transfers its management authority to shareholders, valid only if it is in the certificate of incorporation, all incorporators or holders of record of all outstanding shares authorised it, and subsequent shares go only to persons with knowledge or notice. Section 620(c) then voids it once the shares are listed or regularly quoted over the counter.

Are share transfer restrictions automatically enforceable in Delaware?

No. Under 8 Del. C. § 202(a), a written restriction on transfer or on the amount of securities a person may own is enforceable against a holder, successor or transferee only if it is noted conspicuously on the share certificate or, for uncertificated shares, contained in the notices given under § 151(f). Without that, the restriction is ineffective except against a person with actual knowledge of it, even though § 202(b) permits it to be created by agreement.

Shareholder Agreement in the US

Delaware amended its General Corporation Law in 2024 to give shareholder agreements a statutory footing they previously lacked: a corporation may now contract directly with current or prospective stockholders to restrict its own actions or require their consent, notwithstanding the rule that the board manages the business. New York takes the opposite approach, making an agreement that restricts the board's discretion valid only if it appears in the certificate of incorporation and every shareholder has authorised it.

Download the US drafting checklist (.docx)Where to read US law

Governing law

The corporate law of the state of incorporation governs voting agreements, transfer restrictions and governance covenants between shareholders and the company.

Delaware General Corporation Law, 8 Del. C. § 122

What a shareholder agreement has to contain in the US

Notwithstanding the board's management authority, a Delaware corporation may make contracts with current or prospective stockholders in that capacity, and may agree to restrict itself from specified actions, to require named persons or bodies to approve before it acts, or to covenant that specified actions will or will not be taken.
8 Del. C. § 122(18)
No provision of such a contract is enforceable against the Delaware corporation to the extent it is contrary to the certificate of incorporation, or would be contrary to Delaware law if included in the certificate.
8 Del. C. § 122(18)
Two or more Delaware stockholders may agree in writing, signed by the parties, that their shares will be voted as provided in the agreement or as determined by an agreed procedure, and the section does not invalidate any other lawful voting agreement or irrevocable proxy.
8 Del. C. § 218(c) and (d)
A Delaware restriction on transfer or on the amount of securities any person may own is enforceable against a holder, successor or transferee only if noted conspicuously on the certificate or, for uncertificated shares, contained in the notices given under § 151(f); otherwise it is ineffective except against a person with actual knowledge.
8 Del. C. § 202(a)
In New York a provision that improperly restricts the board in managing the business, or transfers management to shareholders, is valid only if it appears in the certificate of incorporation, all incorporators or holders of record of all outstanding shares authorised it, and later shares go only to persons with knowledge or notice of it.
N.Y. Business Corporation Law § 620(b)

Form, notarisation and registration

A New York shareholders' voting agreement itself needs only to be in writing and signed by the parties to bind how their shares are voted.
N.Y. Business Corporation Law § 620(a)

What catches drafters out

The New York board-restriction route stops working once the company lists: a provision authorised under § 620(b) is valid only so long as no shares are listed on a national securities exchange or regularly quoted over the counter.
N.Y. Business Corporation Law § 620(c)