Two founders.

One idea.

A quick conversation:

“Let's do 50/50.”

Feels fair.

Until six months later, when one founder is building the product, talking to customers, raising money, working nights—and the other is barely involved.

Now that 50/50 split doesn't feel so fair anymore.

And this is where many startups make their first major mistake.

They divide equity based on the idea instead of the contribution.

An idea is valuable.

But an idea alone doesn't build a company.

A company is built through:

Two people can start with the same idea and create completely different outcomes.

Because the difference isn't the idea.

It's what happens after the idea.

Here's a simple way to think about it.

Are both founders working full-time?

Or is one working 60 hours a week while the other contributes 5?

Time isn't everything—but commitment matters.

Who is actually turning the idea into a company?

Who is:

Because execution creates value.

Sometimes one founder brings a skill that would otherwise take years to develop.

Technical expertise.

Industry knowledge.

Regulatory experience.

Product expertise.

That contribution matters.

Who is putting their own money into the company?

Who is taking a lower salary?

Who is giving up a job or other opportunities?

Risk has a cost.

And founder equity should account for meaningful risk.

Here's the part founders often underestimate.

A founder who can bring:

customers + partnerships + hiring + distribution

can be incredibly valuable.

Because building something is only half the battle.

Getting it into people's hands is the other half.

There's a massive difference between:

and

If one founder owns engineering, another owns growth, and another owns fundraising, the equity conversation should reflect those responsibilities.

Here's the uncomfortable truth:

50/50 is equal.

But equal doesn't automatically mean fair.

Imagine this:

Founder A

→ Full-time
→ Builds the product
→ Leads engineering
→ Handles technical hiring
→ Talks to customers
→ Takes most of the execution responsibility

Founder B

→ Part-time
→ Contributed the original idea
→ Makes occasional introductions
→ Has limited ongoing responsibility

Should they automatically own the same percentage?

Not necessarily.

And that doesn't mean Founder B isn't valuable.

It means the founders need to have an honest conversation about what each person is actually contributing.

Before deciding percentages, have every founder independently rate themselves from 1–10 on:

Then compare the answers.

The goal isn't to mathematically calculate:

“You scored 72, so you get 72%.”

That's not how it works.

The goal is to expose the uncomfortable conversations before they become expensive problems.

There's another important piece:

Founder equity shouldn't necessarily become permanently yours on Day 1.

A vesting structure helps protect the company if someone leaves early.

A common startup structure is 4-year vesting with a 1-year cliff, although the right arrangement depends on the company, jurisdiction, and specific circumstances.

The principle is simple:

Long-term ownership should be connected to long-term contribution.

Don't ask:

Ask:

And more importantly:

Because startups aren't built on what happened during the first conversation.

They're built on what happens after everyone gets tired, the product breaks, customers say no, and the company runs out of easy answers.

That's when contribution really shows.

Don't split equity just to avoid an uncomfortable conversation today.

Have the uncomfortable conversation now—

or have a much more expensive one later.

Your equity agreement should answer three things:

Who is building?

Who is taking the risk?

Who is committing for the long term?

Because:

Build the company.
Document the contribution.
Align the ownership.

— AktBook