Founders Letter

Dear Prospective Investor,

IBKR aims to provide an exceptionally inexpensive and versatile platform for our clients to manage their finances.

It is vitally important to us that our clients be better equipped, pay lower prices, and have other advantages so as to generate higher returns than the customers of other brokers.

In part, we achieve these goals by getting frequent feedback and advice, and by otherwise working with our users. Owning our shares provides increased motivation for our clients to work with us toward these goals.

Investment by passive investors, and by others who do not use our platform, tends to cause a run up in our share price. This makes it more difficult for our clients to purchase our shares.

You may be considering investing in IBKR. We would like to ask you not to buy our shares unless you become an active user of our platform prior to doing so.

Sincerely yours,

Thomas Peterffy