If you ever had a broker give a withdrawn member a hassle about the cost basis of shares transferred in a withdrawal, ICLUBcentral now has a memo posted on their website with references to the tax code explaining why the cost basis data on a Withdrawal Distribution Report is accurate and complies with the tax code for this situation.
The memo is on the ICLUBcentral website at https://www.iclub.com/faq/Home/Article?id=672. A pdf version can be found at https://www.iclub.com/tps/ICLUBcentral-StockTransferBasisMemo.pdf . A link to the FAQ version is also found on the myICLUB Withdrawal Distribution Report, if the withdrawal included transferred securities.
By-the-way, you can find examples of cost basis determinations for transferred property from a partnership to a partner in IRS Publication 541-Partnerships.

Russell Malley