Sarah C. Haan has posted “Opaque Transparency: Outside
Spending and Disclosure by Privately-Held Business Entities in 2012 and Beyond”
on SSRN.  Here is a portion of the
abstract:

In this Article, I analyze data on outside spending from the
treasuries of for-profit business entities in the 2012 federal election – the
very spending unleashed by Citizens United v. FEC. I find that the majority of
reported outside spending came from privately-held, not publicly-held
companies, including a significant proportion of unincorporated business
entities such as LLCs, and that more than forty percent of spending by
privately-held businesses was characterized by opaque transparency: Though
fully disclosed under existing campaign finance disclosure laws, something
about the origin of the money was obscured. This happened when political
expenditures were spread among affiliated business-donors, typically donating
similar amounts to the same recipient(s) on similar dates, and when for-profit
business entities were used as shadow money conduits. I also argue that, due to
differences between access-oriented and replacement-oriented electoral
strategies, for-profit businesses engaged in outside spending in a federal
election are likely to be experiencing insider expropriation. The expropriation
of a business entity’s political voice by a controlling person is another
potential

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