Do you have your lottery tickets?

The Mega Millions jackpot is poised to break the $1 billion mark for Friday night's drawing, kicking off a ticket-buying frenzy.

Many of these tickets are purchased as part of an office pool.

So, what happens if your office hits the lucky numbers? Whatever it is, be sure to get it in writing, first.

That's the advice Chicago lawyer Michael Haugh shared on Wednesday with USA Today.

Haugh represented 12 coworkers from the Pita Pan Old World Bakery in Chicago Heights, Illinois, who won a $118 million lottery in 2012. But according to reports, 11 more coworkers came forward, insisting they were part of that workplace lottery pool.

It took three years to settle the dispute, with the original 12, calling themselves the Dirty Dozen, taking home $6 million each and six others splitting $13.8 million.

"The parties should sign a written contract, identifying each participant," Haugh said. "Money has a way of corrupting people."

While Haugh encourages a contract, Illinois lottery officials, where this particular incident occurred, recommends participating in pools only with people you know and trust. The pool leader should also be diligent in tracking members, collecting money and monitoring winnings.

And it doesn't hurt to give photocopies of the front and back of each ticket to participants.

Stories of office pools gone awry are plentiful, like the case of Americo Lopes in New Jersey.

Lopes was part of a group of construction workers who had pooled their money together, giving it to Lopes.

In November 2009, Lopes bought a Mega Millions ticket that won - and told none of his buddies. He cashed the $38.5-million ticket, got a check for $17.4 million, and quit his job, telling everyone he needed foot surgery.

Later, one member of the group heard he'd won the lottery, did a little checking, and discovered the truth.

In March 2012, a jury in Union County, New Jersey ordered Lopes to share the winnings with the five former co-workers.

It's an understatement to say a jackpot the size of Friday's Mega Millions drawing would be life changing -- so much so that it might be a good idea for the winner to remain anonymous.

But is that possible?

"The best thing a person can do is buy a ticket in one of the six states that don't require you to come forward," Marty King, partner with law firm Gorman & Williams in Maryland, told Today. "That means you won't have to go to the press conference with the big oversized check and show your face."

Those states are Delaware, Kansas, Maryland, North Dakota, Ohio and South Carolina.

Other recommendations include: