Can a buyer claim I broke an LOI just by continuing normal business decisions?

Generally not, unless your LOI specifically includes an interim covenant restricting how you run the business while the deal is pending — a common feature of full purchase agreements, but less standard in an LOI itself. Ordinary decisions in the usual course of business, made the way you'd have made them regardless of the pending sale, don't typically breach a standard LOI, since the document usually isn't meant to freeze how you operate before a definitive agreement exists.

The nuance is that some LOIs do include limited interim covenants — for example, agreeing not to take on significant new debt, alter major contracts, or make unusual changes outside the ordinary course while the deal is pending. If your LOI contains language like that, and a decision falls outside what's normal for your business, a buyer could have a genuine argument, though a routine decision consistent with how you've always run things generally wouldn't.

Before assuming any business decision is safe, or that a buyer's claim has no basis, check whether your LOI actually contains this kind of interim restriction. A Treadstone business lawyer can confirm what, if anything, it actually limits.