Under the Model Business Corporation Act, which most states follow in some form, the quorum requirements for board and shareholder meetings are a majority of directors for the board and a majority of the voting shares for shareholders. Fall below either threshold and the meeting can still happen, but nothing voted on there binds the corporation.
Board of Directors: The Default Threshold
MBCA Section 8.24 sets board quorum at a majority of the fixed number of directors if the corporation has a fixed board size, or a majority of the prescribed number if the board uses a variable-range structure.1LexisNexis. Model Business Corporation Act Official Text A nine-member board needs five directors. A seven-member board needs four.
Directors do not have to sit in the same room. MBCA Section 8.20 allows participation by any communication method that lets all directors hear each other simultaneously throughout the meeting, and a director on a video or phone connection counts as present in person.1LexisNexis. Model Business Corporation Act Official Text “Simultaneously” is doing real work in that sentence. A one-way audio feed, or a connection that drops in and out, may not satisfy the standard.
Once quorum is in place, the default voting rule is an affirmative vote of a majority of the directors present. On a nine-member board where five directors show up, three yes votes carry a matter unless the articles or bylaws require more.
Shareholder Meetings: Voting Power, Not Headcount
Shareholder quorum turns on shares rather than people. Under MBCA Section 7.25, a quorum exists when a majority of the shares entitled to vote on a matter are represented at the meeting. A company with 100,000 voting shares needs holders of at least 50,001 shares present or represented by proxy.
Proxies carry most of the weight at any sizable company, because most shareholders never attend in person. They authorize someone else to vote their shares by signing a proxy form. Federal regulations prohibit undated proxies and limit each proxy’s authority to a single meeting and its adjournments.2eCFR. 17 CFR Part 240 Subpart A – Regulation 14A Solicitation of Proxies State law sets default expiration periods when the proxy itself is silent, commonly ranging from 11 months to three years.
How the Numbers Are Counted
Counting Directors
The denominator for board quorum is the total number of authorized director seats, not the number currently filled. If the bylaws authorize nine directors and two seats are vacant, quorum is still five. A depleted board cannot concentrate power in fewer hands simply by leaving vacancies open. The MBCA carves out a narrow exception for variable-range boards with no prescribed number, where quorum is based on the directors in office immediately before the meeting begins.1LexisNexis. Model Business Corporation Act Official Text
Counting Shares
For shareholders, the denominator is the number of outstanding shares entitled to vote, not the number of authorized shares. Treasury shares, which the corporation has repurchased and holds itself, are excluded entirely. They are not outstanding, carry no voting rights, and count toward neither the quorum denominator nor the numerator.
Proxy documents are checked against the official shareholder list as of the record date, the cutoff the board sets for determining who may vote. A proxy signed by someone who sold their shares before the record date is worthless. A proxy signed by someone who bought shares after it is equally invalid.
Losing Quorum During the Meeting
Board meetings and shareholder meetings handle mid-session departures very differently, and the two rules are easy to confuse.
At a board meeting, quorum must generally be present at the moment a vote is taken. If two directors leave a nine-member meeting after the opening roll call, the remaining directors may no longer have quorum, and anything they vote on after that point is open to challenge. The chair should stop business and announce the loss of quorum. Any director can raise the issue if the chair does not.
Shareholder meetings work the opposite way. Once a share is represented for any purpose at the start of the meeting, it stays counted for quorum for the rest of the session, including any adjournment. Shareholders cannot break quorum by walking out before a controversial vote. If the initial threshold was met and documented, the meeting remains valid even if half the room leaves after the opening gavel.
Conflicted Directors Still Count
A director with a personal financial stake in a matter the board is voting on generally still counts toward quorum. Otherwise, a single conflict could paralyze the board. On a five-member board that needs three for quorum, excluding two conflicted directors from the count would make quorum impossible.
That does not mean conflicted directors can vote through their own deals. The protection sits in separate conflict-of-interest procedures: approval by a majority of disinterested directors informed of the material facts, approval by shareholders, or a showing that the transaction was fair to the corporation when authorized. Quorum and voting are doing different jobs.
Changing the Default
The majority rule is a default. Corporations can raise or lower quorum through their articles of incorporation or bylaws. Most states set a floor, typically one-third of directors for board meetings and one-third of voting shares for shareholder meetings, so a tiny minority cannot run the company.
Raising the bar is more common than lowering it, especially for high-stakes decisions. Articles of incorporation sometimes require two-thirds of directors present before the board can approve a merger, sell substantially all assets, or amend the bylaws. These supermajority provisions act as a structural check on hasty action.
For shareholder meetings, the board cannot change quorum unilaterally. A bylaw imposing a supermajority quorum or voting requirement on shareholders can only be adopted if the articles of incorporation authorize it, and the amendment itself must satisfy whichever threshold is higher: the existing quorum and vote requirement, or the proposed new one. Once adopted, the board alone cannot repeal a supermajority shareholder requirement.
Written Consent Instead of a Meeting
A corporation can act without a meeting, which sidesteps the quorum question entirely.
Under MBCA Section 8.21, the board can act by written consent if every director signs a document describing the action. Consent must be unanimous; one refusal defeats it. A director can withdraw consent before all signatures are collected, so timing matters. A signed consent has the same legal effect as a vote at a meeting.1LexisNexis. Model Business Corporation Act Official Text
Under MBCA Section 7.04, shareholder action without a meeting also defaults to unanimous written consent. Every shareholder entitled to vote must sign within 60 days of the first signature or the consent expires.1LexisNexis. Model Business Corporation Act Official Text For any company with more than a handful of owners, that is a high bar.
Some states take a different approach. The articles of incorporation can authorize shareholder action by less-than-unanimous written consent, requiring only the number of votes that would have been needed at a meeting. That makes written consent workable for companies with dispersed ownership, and it also means minority shareholders can be bound by decisions made without any meeting at all. Check the articles to see which rule applies.
What Happens If No Quorum Is Reached
A meeting without quorum is sharply limited. No substantive votes, no resolutions, no binding decisions. Push a vote through anyway and the action is voidable: a court can unwind it, and contracts the corporation signed on the strength of the unauthorized vote are exposed.
The standard move is to adjourn. The members present can reschedule to a later date. If the new date and time are announced before the session ends, the corporation can usually skip a fresh round of formal notices.
If a defect is discovered after the fact, most states provide a process to ratify defective corporate actions. The board reconvenes with a proper quorum, identifies the defective action and the nature of the authorization failure, and votes to ratify using the same quorum and voting requirements that should have applied originally. If shareholder approval would have been required, the shareholders must also ratify. Once properly ratified, the action is treated as valid retroactively from the date it was originally taken. Opponents have a limited window, often around 120 days, to challenge the ratification in court.