How Many Angels Will Fit...?
"Angel rounds need a lead investor, just like venture rounds. Most lead angels drag along a couple of their friends. I like to look for this lead group to take between 40% and 100% of the deal. So - if you can get a small angel group to take the entire deal, you can probably get away with three-ish angels. If you are at the 40% level, you are probably at nine-ish angels.
Remember that angels can (and should) bring a lot more than money to a deal, so the actual number is less important than the value you are getting. You won't get 100% participation (at best - you'll get 50% - more likely less than 33%) - most angels talk a good game but few deliver because they've got other priorities and interests. This is another argument for a larger number (nine-ish.)"
From Feld Thoughts