We can do this:
1. Numerosity - enough plaintiffs to make class action an efficient way to handle the claim.
2. Commonality - common issues of fact and law for each claimant
3. Adequacy of Class Rep - the person who is the class representative needs to have claims that are the same as the class members and that they are capable of serving as the representative.
4. Adequacy of Counsel - that the law firm representing the class has sufficient skill and resources to represent the class.
A certified class action suit is one brought on behalf of a large (3 or more) group of people as plaintiffs who have suffered some similar harm from the same actions of the defendant or defendants