The nonpartisan Office of Congressional Ethics had found that 12 corporations owned and operated by the same group of individuals each donated $5,000 to the Alaska Republican's legal defense fund.
The Ethics Committee agreed but also found that each company was a distinct legal entity. The committee, in a statement Tuesday, concluded the contributions were allowed under regulations.
However, the committee also cited concern that the "identical ownership" of the companies challenged the contribution limit set out by regulations.
It says it has revised regulations for legal expense funds, to take effect next month.