Meaning of hash symbol in pin name

I'm reading the datasheet of a PSRAM (available here). In the top-right hand corner all the pins are listed. Some of the pin names end with a hash, e.g. LB#, OE#.

What does the # notation mean for pins?

Answer

I suppose it means active-low logic, usually indicated by an overscore. Signals like WE#, CE#, LB# and UB# are typically active-low. In datasheets you'll see them as $\overline{\mathrm{WE}}$, $\overline{\mathrm{CE}}$, $\overline{\mathrm{LB}}$ and $\overline{\mathrm{UB}}$.