lentinman: the 15% rule is a good one but may not be sophisticated enough to catch the enormous gyrations in illiquid stocks related to huge bid/ask spreads and tiny volume. Perhaps in the next contest the issue should be more thoroughly addressed.
For example, in the case of GAMM, the bid/ask spread was .50/1.39 for a substantial period of time yesterday afternoon, and at the extreme was briefly at .50/4.75 ! Of the 40k shares traded yesterday only a mere 1950 shares changed hands at over $0.70. Essentially the trades over $0.70 were all just 'window dressing' at the ask and do not represent any significant liquidity to sell at those prices.
If the opening trade on Monday is a buy for a mere 100 shares at 1.50, yet the bid/ask spread is still .50/1.50, then the Friday close becomes a valid price for purposes of the contest. But if the opening trade is a 'sell' at .50, then then Friday's closing price becomes invalid for trading. That leaves a lot to a 'chance' first trade on Monday morning, and in any case fails to address the lack of liquidity (so far) at prices above $0.70.
I don't mean to diminish or reject the fantastic gains realized by SSKILLZ1 and others who own GAMM in the contest, but do feel this issue needs to be further addressed in the next contest, to the extent that we are trying to emulate real life investing with significant sums of money ....