Table: How to Fix Them

-- Don't let companies match 401(k) contributions with shares in an ESOP, because such shares are locked up until age 50.

-- Bar companies from requiring workers to buy company stock. If a company gives stock as a match, allow employees to sell a year after vesting.

-- Educational materials and plan statements should point out the risks of concentrating narrowly in company stock.

-- Company-sponsored investment advisers should be required to assess an individual employee's risk of overconcentration in company stock.

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