how many bundle giveaways in a row lock CV gain?

It isn't a number, but based on non bundle value

Max value from bundle games is 20% of your non bundle value. The first $25 of bundle games will count as bundle value. That will cap it at $30 if you don't give non bundle titles. For every $1 of non bundle games, you can get back 20 cents of the bundle value. $10 non bundle game = $2 bundle value included.

1. Give away games for the sake of making someone happy,not for getting CV. If you're trying to improve your chances at making your library larger,you're better off trading all those keys than giving them away.

2. CV is re-calculated from your first giveaway frequently,meaning the order of your giveaways doesn't matter.

3. CV has 2 pools: Normal pool and bundle pool. Giving away bundle games will increase your bundle pool cv,giving away non-bundled games will increase you normal cv. You can view the list of bundeled games here. When creating a giveaway for a bundeled title,notice the small asterisk - it means that the listed game was bundeled. Note that this list is not update automatically,so naturally it takes some time for it to update and it won't contain the latest bundles - but if you give away a game you bought in a bundle,the next time your CV is re-calculated after said game being added to the list,your gained cv will be lost from the normal cv pool and transferred to the bundle cv pool.
   (Note: bundle games have a date attached to them,so if I buy a game that was never bundeled before,and create a giveaway for it today,and tomorrow it is featured in a bundle - I will get normal cv. Once a game has been bundeled once,you can never get normal cv from it anymore from creating giveaways after that,even if you buy it from the steam store for full price.)

4. "Actual" CV is calculated as so: 100% of normal cv + "bundle contribution". Bundle contribution is 100% of bundle cv,However: the amount of "actual" cv you gain from the bundle cv cannot exceed 20% of your normal cv. For example,if Bob has given away 100$ of normal cv,and 100$ of bundle cv,his actual cv will be 100+20. If he gives away a 10$ normal cv game next,his cv will be 110+22. If he gives away a 90$ game after that,his cv will be 200+40. To calculate tour bundle contribution to your actual cv - that is,how much of your bundle cv will go towards your actual cv,use the following function: [Minimum between (normal cv / 5) and (bundle cv)].

5. As a bonus: to encourage users to give away games(and not have them run off because they gave away a bundle game and got zero cv),your first 25$ worth of bundle cv is removed from your bundle cv pool and transferred to your normal cv poll,as if you have given a normal,not bundled game. This is a one-time bonus and will only work for your first 25$ bundle cv - regardless of whatever you earn it from making 25 1$ giveaways or 1 60$ giveaway. To clarify - if your first giveaway if a 60$ bundle game,your actual cv will be as so - Normal cv = 25$,bundle cv=35$,bundle cv contribution to actual cv = minimum (25/5,35)=5. Normal cv+bundle contribution=25+5=30. You will also have a spare "30$ of leftover bundle cv",which will only go to your actual cv if you giveaway 150$ in normal games(so your total cv gained from giving away extra 150$ in normal games would be 180$,bringing your total to 210$).

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