From Nov. 28 to Dec. 1, the dYdX ecosystem will unlock 150 million DYDX tokens. This amount, which is equivalent to $521 million (USD), represents nearly 85% of the currency's circulating supply. This is shown by the data from the TokenUnlocks browser.

The majority of these DYDX tokens had been locked by investors (46% of the circulating supply), founders, employees, advisors and consultants (25%), and future employees (11%). Meanwhile, the rest is from trading rewards (0.88%) and liquidity provider (0.32).
This means that there could be downward pressure on the DYDX market should those who receive the tokens sell them. That is why, before unlocking a crypto asset, sometimes some of its holders tend to get rid of their coins for fear of perceiving a depreciation. And that may be what is happening now.
The price of DYDX has been going down on the approach of the massive token release. It registered a 15% drop in the last three days, going from trading at $3.73 to $3.17