Once, upon filing his tax return, Albert Einstein famously joked, “This is too difficult for a mathematician. It takes a philosopher.”

If one of history’s greatest minds struggled to understand the myriad tax rules that existed in his day—short form compared with today—how are business owners embarking on the sale of their companies supposed to know what to do when faced with the tax decisions related to the transaction?

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The answer, of course, is to rely on experts, although tax specialists admit it’s getting increasingly difficult for even them to navigate all the regulations. “It really is as complicated as it appears,” says James Blackwell, managing partner for BDO Canada in Orangeville, Ont. “I’ve been doing tax work for some 20-odd years, and it’s getting worse all the time.”

And gray areas are on the rise, making the process even more difficult for owners.

Although each seller’s circumstances are unique, there are some general points to consider.

Shares benefit the seller

The principal decision is usually whether to sell shares of the business or its assets; or, in some cases, a combination of both.

“In general, it’s an advantage for a vendor to sell the shares,” says Jim Murdoch, a partner in the Toronto office of Thorsteinssons LLP. “The opposite is generally true for the purchasers. They usually get a better deal out of buying the assets. But you can’t say that 100% of the time.”

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A primary benefit of a shares transaction is the potential for each share seller to claim up to a $750,000 capital gains tax exemption. This is a particularly advantageous strategy if the shareholders are related. “I’ve seen transactions where proper tax planning resulted in accessing six or eight capital gains exemptions for family members,” says Bryan Allendorf, regional tax leader in the Markham, Ont., office of MNP. “Parents, children, grandchildren. They could potentially shelter $4 million or $5 million of gain.”

Of course, there are certain conditions. One is that they must pay fair-market value for the shares. And they need to have held them for at least 24 months prior to sale (although there are a few exceptions).

Also, to be eligible for a capital gains exemption, 50% or more of the firm’s assets have to relate to its active business for two years leading up to the sale.

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“Sellers are forced to take out their redundant assets not used in the active business,” says Blackwell. The number increases to 90% on the day of the sale. Blair Corkum, founder of Corkum & Arsenault in Charlottetown, P.E.I., has a client who’s currently struggling with the redundant assets problem.

A couple of years ago, the client purchased land through his company. “I warned him at the time that the land, and some other investments, could make him ineligible for the exemption if he wanted to sell the company in the next two years. He said that wouldn’t happen. Then someone came along and made him an offer.”