In the market depth image shown, watching in real-time, I noticed this behavior. The ask volume (260,000) wouldn't change even though transactions on the right kept hitting the ask price in volumes greater than the 260,000 displayed. Is is possible 260,000 number isn't a true representation? If so, how can one see the true volume for sale at the ask?
I'm not sure it makes a difference that this is a penny stock as I've noticed the same behavior on non-penny stocks.
I don't know about the Pink Sheets but on major exchanges, hiiden orders offer traders the ability to disguise the size of their order, displaying only the order size that they want.
Iceberg orders are large orders that are split up into lots or small sized limit orders. They are split up into visible and hidden parts, with the latter transitioning to visibility after the former type of order is executed.
They are typically placed by large institutional investors to avoid disrupting trading markets with a single, large order.
