The Ins and Outs of Shareholders Agreements and Company Constitutions (2026 Updated)

If you’re building a company in Australia with a co-founder, business partner, friends, family, or investors, there’s a good chance you’ll hear the same advice early on: “Make sure you have your legal documents sorted.”

In practice, that usually means two core documents get a lot of attention:

• a Shareholders Agreement, and
• a Company Constitution.

They’re often talked about together, but they do different jobs. One is a contract between shareholders (and usually the company). The other is the company’s internal rulebook. If you mix them up or leave gaps between them, you can accidentally create confusion right at the moment you need clarity most (like when you’re raising capital, making key decisions, or handling a founder exit).

Below, we’ll break down what each document does, how they work together, and what to think about in 2026 when you’re setting up (or updating) your company’s legal foundations.

What Is A Shareholders Agreement (And When Do You Need One)?

A Shareholders Agreement is a private contract that sets out the rules of the relationship between shareholders, and usually also the relationship between shareholders and the company.

Even if you’re working with someone you trust completely, this document is less about “expecting a dispute” and more about making sure everyone is on the same page while things are going well.

Common Situations Where A Shareholders Agreement Makes Sense

You don’t legally “have to” have one in most cases, but it’s strongly worth considering if:

• you have more than one shareholder (even if it’s just two founders)
• shareholders will be contributing different amounts of money, time, or intellectual property
• you plan to bring in investors (now or later)
• you want clear rules around exits, transfers, and disputes
• you want to protect the business if someone stops working in it

What A Shareholders Agreement Usually Covers

Every company is different, but a well-drafted Shareholders Agreement often deals with:

• Ownership and capital: who owns what, what’s been contributed, and how future funding works
• Decision-making: what decisions need a simple majority vs unanimous approval
• Director appointments: who can appoint/remove directors and how the board operates
• Dividend policy: whether profits are reinvested or distributed, and when
• Share transfers and exits: what happens if someone wants to sell, leaves the business, or passes away
• Minority protections: how minority shareholders are protected from unfair decisions
• Deadlock and dispute resolution: practical mechanisms to avoid costly litigation
• Restraints and confidentiality: protecting the business if someone leaves

If you’re reading this and thinking “we’d just work it out if something happened,” that’s a very normal starting point. The problem is that when stress hits (financial pressure, burnout, investor deadlines), “working it out” can become much harder than anyone expects.

2026 Reality Check: What Shareholders Disputes Usually Look Like

Most disputes aren’t dramatic at first. They usually start with everyday operational questions, like:

• Can one founder hire staff without asking the other?
• Who approves a big software or marketing spend?
• What happens if one shareholder stops contributing but still owns the same percentage?
• If you get an acquisition offer, can one shareholder block the sale?

A Shareholders Agreement gives you a clear process for these moments, so you’re not negotiating from scratch when time matters.

What Is A Company Constitution (And Why Does It Matter)?

A Company Constitution is a document that sets out the rules for how your company is governed and run. It’s tied closely to the Corporations Act 2001 (Cth) and works alongside other governance tools (like board resolutions and shareholder resolutions).

You can think of a constitution as the “operating manual” for the company itself. It’s not just about the shareholders personally-it’s about the company’s internal mechanics.

Is A Constitution Mandatory In Australia?

Not always. Some companies operate using the replaceable rules under the Corporations Act instead of a tailored constitution.

But many companies still adopt a constitution because it gives you more control and can be tailored to suit how your business actually operates (especially if you’re planning to grow, raise funds, or have more complex share structures).

This usually becomes part of your broader company set up planning, alongside decisions like directors, shareholders, and how you’ll manage legal risk from day one.

What A Constitution Typically Covers

While constitutions vary, they often include provisions about:

• share classes and rights: what different shares can do (e.g. voting vs non-voting)
• director powers and meetings: how directors can make decisions and what approvals are needed
• shareholder meetings: notice requirements, quorum, and voting rules
• issuing shares: processes for issuing new shares and setting issue prices
• transferring shares: restrictions or approvals required
• execution of documents: how the company signs documents (often aligning with section 127 execution)

If you’re considering different equity arrangements, it’s also worth understanding the practical limits and strategy around equity-like how many shares your company can issue and what that means for future fundraising and founder ownership.

Shareholders Agreement Vs Constitution: What’s The Difference (And Why Do You Need Both)?

This is where many founders get stuck, so let’s make it simple.

The Core Difference

• A constitution is an internal governance document for the company.
• A shareholders agreement is a private contract setting out the deal between shareholders (and often the company too).

They overlap in some areas (like issuing shares and transferring shares), but they’re not interchangeable.

How They Work Together In Practice

In a well-structured setup:

• the constitution sets the baseline governance rules that apply to the company, and
• the shareholders agreement adds extra commercial detail and relationship rules (like deadlock processes, founder vesting, and exit mechanics) that you generally wouldn’t want (or be able) to capture cleanly in a constitution alone.

Just as importantly, they should be consistent. If the constitution says one thing and the shareholders agreement says another, you can end up with uncertainty about which rule applies-and that’s usually the opposite of what you want when making high-stakes decisions.

Where Founders Commonly Get Caught Out

Some common problem areas we see include:

• Issuing new shares: the constitution allows directors to issue shares broadly, but the shareholders agreement says existing shareholders must approve
• Transfers: one document has strong transfer restrictions but the other is silent (or inconsistent)
• Decision thresholds: the constitution sets ordinary resolutions, but the shareholders agreement requires unanimous consent for “reserved matters”
• Investor expectations: an investor asks for certain controls, but your documents can’t accommodate them without amendments

The goal isn’t to make your company paperwork complicated. The goal is to make your company decision-making predictable.

Key Clauses To Get Right In 2026 (Especially If You Want To Raise Money Or Scale)

If you’re updating your documents (or doing them properly for the first time), these are some of the clauses that tend to matter most in 2026-particularly for startups and growth-focused businesses.

1. Reserved Matters (Who Must Approve What?)

Reserved matters are decisions that can’t be made by one person alone. They usually require either:

• board approval,
• a shareholder vote (majority/special/unanimous), or
• approval from a particular shareholder or class (common in investor deals).

This is one of the clearest ways to prevent misunderstandings between founders and protect minority shareholders.

2. Share Transfers, Pre-Emption Rights, And Exits

If someone wants to leave the business, you want a process that’s fair, structured, and doesn’t disrupt operations.

For example, you might include:

• pre-emption rights: existing shareholders get the first right to buy shares before they’re sold to outsiders
• drag-along and tag-along rights: practical rules for handling a company sale so one shareholder can’t derail (or be left behind in) an exit
• valuation mechanisms: how shares are priced if someone leaves

Transfers can get even more sensitive when they involve family arrangements. If that’s your situation, it’s worth thinking early about the practical steps around transferring shares to family members, and how your company documents may restrict or manage that.

3. Founder Vesting And “Good Leaver / Bad Leaver” Provisions

Vesting is a common way to protect the company if a founder leaves early. Rather than “earning” all their equity on day one, equity can vest over time (or be subject to clawback) if they don’t remain involved for an agreed period.

Good leaver / bad leaver provisions are often used alongside vesting to deal with different exit scenarios (for example: leaving due to illness vs leaving to compete with the business).

4. Dividends Vs Reinvestment (And What Happens When You Disagree)

One founder might want to reinvest profits to grow. Another might want dividends. Neither is “wrong,” but without a clear agreement, this can become a recurring conflict.

A good document sets expectations and a process for deciding what happens year to year.

5. Deadlock Resolution (Because 50/50 Companies Are Common)

If you have two shareholders with 50/50 ownership, deadlocks can happen easily-even when both people are acting in good faith.

Deadlock clauses might include steps like:

• structured negotiation between founders
• mediation before any court action
• a buy-sell mechanism (sometimes called a “shotgun clause”)
• chairperson casting vote (more common at board level)

The aim is to keep the business moving, not “pick a winner.”

6. Director And Shareholder Roles (Avoid Blurring The Lines)

In smaller companies, people often wear multiple hats: founder, shareholder, director, employee. That’s normal, but it can create confusion if your documents don’t separate those roles clearly.

If you want a clearer foundation, it helps to understand the difference between a director and a shareholder, because the legal duties and decision-making pathways aren’t always the same.

How To Choose The Right Setup (And Keep It Updated As You Grow)

When you’re early-stage, it’s tempting to keep things “simple” by using generic templates or putting decisions off until later.

The risk is that later is usually when:

• you’re raising money and investors want certainty
• you’re hiring and scaling and need faster decision-making
• someone wants to exit, or there’s a disagreement about direction

That’s why we generally encourage you to treat your constitution and shareholders agreement as living documents that evolve with your company.

A Practical 2026 Checklist For Founders

If you’re trying to sense-check where you’re at, here are some useful questions to ask:

• Are we planning to bring in investors within the next 6–18 months?
• Do we have a clear plan for what happens if a founder leaves?
• Do we know who can approve big spending, hiring, or borrowing?
• Are we confident our documents match how we actually run the business?
• Do we have any “handshake deals” that should be written down?

When Do You Need To Amend Your Documents?

You may want to update your constitution and/or shareholders agreement when:

• you issue new shares or create a new share class
• you bring in a new co-founder or investor
• you change your board structure
• you start operating in a higher-risk environment (larger contracts, more employees, regulated industry)
• you realise your current documents don’t reflect how decisions are really being made

It’s usually much easier (and cheaper) to tidy things up before a major event-like a capital raise or acquisition-rather than during it.

Don’t Forget The Rest Of Your Legal Foundation

While this article focuses on constitutions and shareholders agreements, they’re only part of running a well-protected company.

Depending on what your business does, you may also need customer terms, IP assignments, employment documents, and privacy compliance. If you’re collecting customer data online (even something as simple as email addresses for a newsletter), a Privacy Policy is often part of doing things properly from the start.

Key Takeaways

• A Shareholders Agreement is a private contract that sets out the relationship rules between shareholders (and usually the company), including decision-making, exits, and dispute resolution.
• A Company Constitution is the company’s internal rulebook, covering governance mechanics like meetings, issuing shares, transfers, and how documents are executed.
• Most growing companies benefit from having both documents, because they serve different purposes and create clearer rules when the business scales or brings in investors.
• Key clauses to focus on in 2026 include reserved matters, transfer and exit rules, founder vesting, dividend policy, and deadlock resolution-especially for 50/50 founder companies.
• Your documents should stay consistent with each other and should be reviewed when you raise capital, issue new shares, change directors, or bring in new shareholders.

If you’d like help putting the right structure in place (or updating what you already have), reach us at 1800 730 617 or team@sprintlaw.com.au for a free, no-obligations chat.