We find that the ideal number of partners is somewhere between four and seven.
The one thing we strongly recommend against is having too many partners and for this reason we’ve capped the amount of partners allowed on a giveaway on DojoMojo at eight.
The reason for this is that during a campaign, every partner is receiving all the email addresses received as people enter the contest. This means that all partners will be sending email communications to these individuals. Individuals are much more likely to grow annoyed and unsubscribe if they receive a bunch of emails at once in a way that feels like spam.
By having fewer partners, they’re less likely to be bombarded with a flood of emails and as a result, are much more likely to open yours.