Yippee! After years of buying a weekly group syndicate lottery ticket at your workplace you have finally won millions. Surely happiness is assured and life from now on is one big party.

Sadly, all too often a big lottery syndicate win ends in tears. Just recently a group of 15 factory workers won $40 million but ended up in a heated court battle when the factory manager argued he had been left out of the split syndicate win.

Allegations flew that someone new was included in the massive payout instead of the manager. It all ended up in court where the big win risked being eaten up in legal fees.

Last year another work syndicate went to court alleging they had been cheated out of a $16 million win when the person who usually bought the ticket said he'd bought two tickets that day – and surprise - the winning ticket was the one he'd bought just for himself. They eventually settled out of court.

In 2010 three mates fought so long over a $13 million Lotto winning ticket that by the end of a fierce court battle there wasn't much left of the win for them to enjoy.

Tony Mitchell at Stacks Law Firm warns there is a lot of trust involved in lottery group syndicates, and it would be wise to plan in advance.

"It's fun to be part of a hopeful collection of friends or colleagues, but when a big win comes, trust can fly out the window," Mr Mitchell, a legal expert in managing assets, said.

"The best way to ensure a group lottery win runs smoothly and is divided fairly is to put down in writing what syndicate members agree to – how much they pay each week or month, who buys the ticket, and how a win will be divided.

"It doesn't have to be a complex legal document, but it should be detailed enough to stand up in court if there is a disagreement.

"In legal language it's called a private agreement. It can set obligations for each member such as who buys the ticket, what happens if a person misses paying for a week, keep a record of who chips in to the syndicate, and how winnings will be divided.

"If you haven't registered as a syndicate with the lottery seller, and the group just has a verbal agreement with the person who buys the ticket then you'll have to hope the ticket buyer shares the winnings as agreed. It's far better to set things down in writing, even if it's a group email."

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