And now, the closing bonus…

The other day, when we announced our own M&A news with Morningstar (MORN), we poked at some of the crazy things we’ve seen over the years in other M&A deals. Well, we’ve just stumbled across a new one at tiny Home Diagnostics (HDIX), which announced its own deal last week to be acquired for $11.50 a share by the Japanese-based Nipro Corp.

Now normally we don’t spend a lot of time looking at companies this small. But we couldn’t help it when we stumbled across what appears to be a new M&A perk: the closing bonus. In both the 8-K that was filed last week and another filing from yesterday, the company disclosed that six of its top executives would receive hefty closing bonuses. In most cases, these closing bonuses exceed the annual salaries that the executives made. For example, President and CEO Joseph Capper’s closing bonus was set at $489K, just shy of his $500K salary. All told, the closing bonuses for the six executives add up to nearly $2 million.

The language the company used to describe these bonuses seemed particularly amusing to us. And the timing — just a day before the deal was announced — was interesting too. Here’s a snip:

On February 2, 2010, to compensate the below-named officers of the Company for the additional services provided by such officers in connection with the due diligence process relating to the Offer and Merger and to provide certain incentives to such officers of the Company to continue to facilitate the transactions contemplated by the Merger Agreement

That’s a fancy way of saying that they’re getting paid extra money to basically do their jobs.

Just to make sure we were right in our hunch that this was a new perk, we decided to search through all filings for the words “closing bonus” and largely came up empty-handed. There were a few examples at mostly smaller companies, including Friend Finder Networks, the online dating site, which scrubbed its IPO last week due to lack of interest. But it’s clearly not a typical part of most deals.

To be fair, Home Diagnostics stock jumped sharply on the news of the deal, nearly doubling. Still, that hasn’t stopped several law firms — we counted at least four — who have announced plans to investigate this deal on behalf of shareholders. Perhaps, they’re also wondering about this new M&A perk.