Willis Tower, we hardly knew thee.

Eleven years have passed since the Willis Group, a London-based insurance broker, purchased the naming rights to the 110-story skyscraper, but the change never truly registered with locals.

Even after the initial outrage quieted to a murmur, many Chicagoans took up passive resistance by pretending the deal never happened. To reply “Oh, you mean the Sears Tower?” to any mention of Willis Tower became a matter of provincial civic pride.

That’s why the only question anyone seemed to care about last month when Aon announced the $30 billion deal to acquire Willis Towers Watson, the Willis Group’s successor, was: Whose sign will hang above the entrance of 233 South Wacker Drive? Aon isn’t saying, and we may not know until the mega-merger closes early next year. In the meantime, let’s rank the most likely possibilities.

1 AON TOWER

It should be a no-brainer: Aon just spent big bucks to vanquish their rival and declare the Willis brand dead. Plus, they’re inheriting a $1 million-a-year contract for the tower’s naming rights through March 2025 along with two five-year renewal options. If they’re paying for it, why wouldn’t Aon etch their name on their new 1,451-foot-high steel-and-glass trophy?

Well, for one: The reigning heavyweight champion of the city’s skyline comes with plenty of baggage, and Aon may not want to relitigate a messy breakup. Following the 2009 Willis deal, local media dedicated an entire news cycle to angry residents who had a skyscraper-sized chip on their shoulder about the loss of the Sears branding. Nearly 100,000 Facebook users joined the People Against the Sears Tower Name Change group and 50,000 more signed the online petition It’sTheSearsTower.com. A company that calls itself the world’s leading provider of risk management may not want to risk Donald Trump’s business strategy of “bad publicity is better than no publicity at all.”

Then again, the potential for bad publicity didn’t stop Aon from stamping their name on 200 E. Randolph Street in 1998. Back then, the white-stone clad building was named for Amoco, though many Chicagoans still called it “Big Stan” in honor of former tenant Standard Oil Company of Indiana.

The existence of the Aon Center adds an extra wrinkle here.

“If they have two big buildings in the same downtown, would they change the Willis Tower to Aon 2? From a brand standpoint, I think that’d add more confusion,” says Kevin Masi, co-founder and chief marketing officer of Torque, a real estate marketing and brand management firm.

There’s also the problem of diminishing returns. The more a name changes, the less impactful it’s likely to be. Consider the White Sox’s home. Over the past few decades, it’s been called Comiskey, U.S. Cellular Field (a.k.a. The Cell), and now, as of 2016, Guaranteed Rate Field. Many fans have rebelled and settled on New Comiskey or simply Sox Park.

“People start to give up once you do this naming roulette that never seems to stop,” says Pete Herrnreiter, vice president of strategy and planning at Motion, a Chicago-based brand and strategic communications agency.

But without a clear-cut secondary option, Aon may still decide that a few bad headlines are worth the added value of naming rights to one of the most iconic buildings in America.

“It’s a very valuable asset in an expanding market in the South Loop,” Masi says. “There’s still a lot of prestige to have your name on a building like that.”

2 233 SOUTH WACKER

In February 2018, the Hearn company decided to remove the John Hancock branding from the famous tower named in 1969 for the insurance company.

More than two years later, there’s still no new naming deal. The twin-antennaed skyscraper is simply known by its address: 875 North Michigan Avenue.

Perhaps Aon will decide to run out the clock on their current deal. After all, no one wants to risk making another Time Magazine list of history’s Top 10 Worst Corporate Name Changes.

3 UNITED TOWER

At 850,000 square-feet, the largest tenant at Willis Tower isn’t its namesake — it’s United Airlines. Considering that the airline giant’s Willis lease extends through 2033, there’s some logic in pushing for buying naming rights. But according to Crain’s, United already had the option to do so last year and passed.

Plus, United already spends millions of dollars a year to have their name plastered all over the home for the Bulls and Blackhawks. Naming rights for sports stadiums is more valuable than corporate office buildings, says Masi.

If you’ve already got the United Center, why bother with the United Tower?

4 SEARS TOWER

On paper, it’s very silly to pay money to rename a building for a past tenant, especially one that’s currently languishing in Chapter 11 bankruptcy. The COVID-19 crisis may prove the final dagger for the long-troubled retail chain.

And yet, the Second Coming of Sears Tower is a dark-horse pick here because of the sheer popularity of such a move in Chicago.

“If Aon gave Chicago back the Sears Tower, it would be a nice gift to the city that would create a lot of goodwill,” Masi says.

It’s a gift that could even be justified by naming it for a man — original founder Richard Warren Sears — not his now-failing business. There could even be a compromise: Aon-Sears Tower, maybe?

Maybe not. In 2012, Aon moved its corporate headquarters from Chicago to London and now employs 50,000 people in 120 countries. Would they really give up the opportunity to market their own name just to generate some headlines and appease disgruntled Chicagoans?

“They may get a blip of community value for calling it Sears, but beyond that, what’s the long-term global strategy there?” Herrnreiter says.

5 TWO-THREE-THREE OR THE WACKER

See #2, but trendier.

These days, it’s all the rage to name new buildings after tedious references to their address or street names (think 1000M for 1000 South Michigan Avenue or The Van Buren at 808 West Van Buren).

But that’s mostly the case for residential condo towers, not corporate office space and retail. And could anyone with a straight face really risk the once-proud Sears Tower being nicknamed “The Wack?”