I run two pools at my workplace.
The first pool is for either Mega Millions or PowerBall, depending upon which one has the bigger jackpot. The number of players can vary because we only play when either jackpot has passed a certain threshold. We usually start playing when either game exceeds $300 million. Sometimes there can be 20 or more people in the pool, but other times there have been as few as 15 people. If you're at work, and you want to play, you're in. If you're not at work and we play, you're not in. If you're at work and choose not to play, that's fine, but you're not in. It's strictly voluntary participation. All players know that if you choose not to get in, or they're not at work when we play, then you're not in the pool on that particular date. If we won a large prize, those that did not play for whatever reason know and understand that they are not in. It matters not if they were out sick or on vacation. Sometimes someone will "cover" a friend who is not at work and put $$ in for them. I'm the person that collects $$ and buys the tickets, therefore I never "cover" for anybody. The pool is open to all comers. I approach most people and collect $$, but I've had people approach me and ask to get in, and they're welcome to get in. If it's PB we are playing, I collect 2 dollars per person. I collect $1 per person for MM. I scan all the tickets I buy, and email a PDF file containing the tickets to everyone who got in. If someone didn't get in for whatever reason, no PDF file will be emailed to that person. All lower tier winnings have been rolled back into the pool. (We won 12 bucks once, so I bought 12 MM tickets with the winnings for the next MM drawing) If we are ever so lucky to win a large prize, I would call a meeting of the group of people who played, and we would have to discuss/decide what we wanted to do as a group.
I run second pool, and there are just eight of us in it. It's closed to other people. The 8 of us chip in either 30 or 40 dollars each to buy raffle tickets. We buy either Connecticut's "SuperDraw" million dollar raffle tickets ($10 each), or Pennsylvania's "Millionaire" raffle, which cost $20 each. Each state runs their respective raffle twice per year. The next one is set for July 4th, 2015. If we play CT's Superdraw, we each throw in 30 bucks, and we buy a total of 24 tickets. If we play PA's Millionaire Raffle, we each throw in 40 bucks and buy 16 tickets. Tickets for each go on sale three months prior to the drawing, so I collect either 10 bucks per month from each member, or I collect 20 bucks twice during the three month period tickets are on sale. Depending upon which raffle we decide to play will determine the total amount each person chips in. The reason we don't have/want more members in this pool is because an 8-way split of one million dollars yields $125,000 for each of us in the pool before taxes. After taxes, we would probably net $80,000 to $85,000. Adding more players to the group would only reduce any winnings further, and we don't want that.
As I mentioned above, the next raffle for both PA and CT is July 4th, 2015. The nice thing about the PA raffle is that each ticket has 4 chances to win a million dollars, as there are 4 one million dollar winners. Odds for this raffle are 125,000 to 1 and in reality, even though we have 16 physical tickets, we really have 64 chances to win a million bucks. CT sells a maximum of 275,000 SuperDraw tickets so the odds there are 275,000 to 1, but there is just one winner of the top prize of a million dollars. So we have 24 chances to win the top prize in CT. My thinking is the guys will want to buy PA's tickets rather than CT's even though it'll cost them a total of 40 bucks. That extra 10 bucks gives us 40 extra chances at a million dollars than we'd have with CT's raffle.