SL stock markets are still completely legal.
All of the gain in funds from a stock market is done by people buying stock, which requires an exact equal input of L$ per L$ gained.
My point is gaining L$ from a human spending L$ is still legal, and all the L$ you gain from a stock market comes from a human spending L$ on the stock.
Because of this, stock markets do not fall under the term of gambling as per LL's rule against gamlbing.
LindeX, the oficial L$ currency market, is its'self a stock market in trading L$.
LL would have to close LindeX (thus killing the sl economy) to make stock markets against the rules.