Fifteen years after opening its doors, Baltimore’s most valuable office tower will pay a full tax bill in 2025.

Based on its assessed value, the 24-story building at 100 International Drive — formerly known as the Legg Mason Tower — is expected to pay more than $4 million to the city this year.

Until now, a controversial tax break waived almost the entirety of its property tax bill each year. Pitched as a crucial incentive for the newly redeveloped neighborhood of Harbor East, the maneuver became part of a corruption probe at City Hall.

Today, the market for office space in Baltimore and across the country is struggling to recover from the COVID-19 pandemic, and several floors are going unused at the Harbor East office tower.

The Paterakis family — founders of H&S Bakery Inc. — redeveloped Harbor East into one of the city’s glitziest neighborhoods in the 1990s and 2000s using a company called H&S Property Development Corp. Formerly an industrial site, Harbor East sits a few blocks west of the family’s bread-baking plant in Fells Point and offers panoramic views from the city’s waterfront.

In the mid-2000s, H&S and officials from the Baltimore Development Corp. worked on a tax break that would keep the financial management firm Legg Mason in Baltimore, The Baltimore Sun reported at the time. Legg Mason had its headquarters in downtown Baltimore and was flirting with leaving the city.

In 2007, the City Council approved the tax break, known as a Payment In Lieu Of Taxes, or PILOT, and the office tower opened in 2009.

That year, a corruption probe engulfed City Hall, and years of prior development deals were scrutinized — including this one.

At age 80, John Paterakis Sr., the founder of H&S Bakery, pleaded guilty to misdemeanor campaign finance violations. Ronald Lipscomb, a developer who had a stake in the project, also pleaded guilty to a similar charge.

Together, they admitted to meeting with then-Councilwoman Helen Holton ahead of the council’s vote on the tax break. Holton brought up their proposed redevelopment of Harbor East, Paterakis told prosecutors. Lipscomb said she asked them to fund a $12,500 political poll. They split the cost, which exceeded the maximum legal contribution amount.

Holton, who chaired the Taxation, Finance and Economic Development Committee, voted in favor of their tax break. Holton was charged with bribery, but those charges were later dismissed. She pleaded no contest to a campaign finance violation.

By that point, the office tower in Harbor East was open for business.

In late 2016, CBRE Global Investors bought a 56% stake in the building from H&S Properties Development Corp. for about $480 per square foot, The Sun reported.

Before the sale could close, the City Council had to lift a profit-sharing agreement with H&S. The firm was supposed to share a quarter of the building’s profit with the city above a 15% return. But the building was never that profitable, and H&S instead extinguished the requirement by making a one-time payment of $1.5 million to the city.

The Abell Foundation sued the city over the PILOT, alleging that the city should have disclosed more financial details about the tax break. The Baltimore-based nonprofit essentially wanted to know: Did the office tower really need the incentive?

But a judge ruled against the Abell Foundation, and the nonprofit lost its appeal of that case last year.

The 2016 transaction broke the record for the price of office space in Baltimore. It valued the tower at nearly $300 million, or close to $400 million today, in inflation-adjusted dollars.

The sale was viewed as the latest sign of Baltimore’s strengthening office market. Instead, it would be its high-water mark.

A few years later, the pandemic accelerated the trend of working from home — something that downtowns and office parks across the country are still grappling with.

The real estate firm Cushman & Wakefield reported this fall that 20.9% of office space across the country is vacant.

Newer office space has been built in Baltimore since the former Legg Mason tower opened in 2009. But even some of those new developments — such as Baltimore Peninsula in South Baltimore — have not been able to find enough tenants for their office space.

According to a report this fall from MacKenzie Commercial Real Estate Services, Baltimore’s office vacancy rate was 22.1%. Much of that office space is located in the city center, which had a 28.8% vacancy rate.

And that doesn’t include office space that is leased but going unused. Many office leases can last several years or longer, creating a secondary market for subleases.

At 100 International Drive, for example, more than one-third of the tower is advertised as available for leasing.