Why not simply say "at cost"? That seems more in line with the author's intent: distributors can charge recipients (at most) the actual cost of providing a copy. Or, to give distributors a profit-based motive to point out that source code is available, perhaps something like "up to 5% over cost".
Posted Jan 10, 2011 3:43 UTC (Mon) by giraffedata (subscriber, #1954)
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The problem with a simple "at cost" is that that can reasonably be interpreted to include the cost of developing the code. It's probably worth a few extra words to make sure those costs are excluded.