It says "Use PokerStars Marketing Code CCPS at sign-up and Bonus Code Stars600 when making a deposit"
Here is information on how it works. It is from this nice article that has a lot of information on Pokerstars Room not just bonus.
https://www.cardschat.com/poker-stars.php
WELCOME BONUS
All new PokerStars real money players, including mobile players, receive a generous Welcome Bonus, up to C$800 when you sign up with Marketing Code CCPS. The bonus consists of a 100% match of a maximum of three deposits made during your first 60 days of play. If you can afford to deposit the entire C$800 on day 1, you should do so. But, if you would rather make a smaller deposit initially and make another deposit or two later, as long as it is within the 60-day time frame, the second and third deposits will also count. Then you can still receive the full C$800 PokerStars deposit bonus or whatever your total qualifying deposits add up to if less. Keep in mind that you are under no obligation to deposit C$800. If you prefer to deposit less, you are free to do so and you will still get a PokerStars welcome bonus, but a smaller one requiring less playthrough to clear.
IMPORTANT: When you first sign up make sure to use marketing code CCPS and when you make your first deposit, use the bonus code Stars600 in order to claim the promotion.
In order to clear this PokerStars bonus, you will need to earn the necessary number of VIP Player Points (VPPs), which you do every time you play with real cash in a ring game or tournament. For every €/$1 that you contribute to the rake in a ring game or pay in tournament fees, you earn 5.5 VPPs. You won't have to wait until you have cleared the entire bonus though to start receiving some of it. Each time you earn 200 VPPs at PokerStars, €/$10 of the pending bonus is released. You are given four months all together to earn enough VPPs to clear the bonus in its entirety.
If you have any questions or still have problems with code please let us know.