Looks like someone has it in for Major League Baseball's stingier franchises.

As a private corporation, MLB and its teams keep their inner financial workings close to the vest, though we have a decent idea of how well the industry does. Player contracts and total payroll amounts are made public, and Forbes does an annual ranking of the most valuable baseball franchises. From that, we know that the New York Yankees' valuation sits at a cool $1.6 billion, with the average club worth just under $500 million.

And so it happened Saturday that the Pittsburgh Pirates lost their 83rd game of 2010, thereby clinching a losing record for the 18th consecutive year. Last season, the Pirates' 17th straight losing season set the all-time mark for futility in the history of major professional American sports. This year, losing in Pittsburgh came of legal age, and that was enough for someone with access to the Pirates' internal financials to leak them to the Associated Press, which ran its story yesterday.

The documents painted a grim picture of a franchise that has continuously been one of MLB's stingiest franchises when it comes to paying players, yet the club has been very profitable for those running it. The Pirates pulled in nearly $30 million in net profit between 2007 and 2008, years they finished last in their division and couldn't muster a seasonal winning percentage more than .420.

However, Deadspin released the mother lode this morning, posting scans of financial documents relating to the Pirates, Tampa Bay Rays, Los Angeles Angels, and Florida Marlins, as well as the Seattle Mariners in a follow-up.

Maury Brown of the excellent Biz of Baseball blog has done a tremendous job of breaking down all the nitty gritty in the Deadspin exclusive. Here are some of the juicier tidbits:

• Of the five teams who had their info leaked, only the Mariners didn't make a profit in a given year, losing $4.5 million in 2008.

• Thanks to the league's generous revenue-sharing program, the Pirates received some $69 million from MLB over the 2008 and 2009 seasons.

• As it relates to revenues received from concessions - which are typically run by outside entities, which then cut the team in on some percentage of the profits - the Marlins made $1.64 per fan in attendance last season.

• The Pirates franchise, for all of its on-field ineptitude, invested some $44 million in player development over the '07 and '08 seasons.

Don't think MLB will sit idly back as this story develops. As CNBC sports business reporter Darren Rovell points out, only a very select few could have had access to these various documents, so the hunt into who leaked this information to the press has only just begun.

*Photo: Flickr/daveynin, CC

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