Workspace Property Trust has delayed its IPO in a move that sheds light on investor interest — or lack thereof — in suburban office real estate.

The company, helmed by former Mack-Cali Realty CEO Thomas Rizk, planned to list its company on the New York Stock Exchange on Monday before a release the same day explaining the indefinite postponement, the Philadelphia Inquirer reports. Workspace cited "current market conditions" as the main reason for delay, promising to "reevaluate options at a later date."

In its initial statement announcing its intent to go public, Workspace cited the maturing millennial population that some believe will inevitably return to the suburbs in droves to raise families, but the pullback may indicate investors did not share such optimism.

Philly's suburbs absorbed 1M SF of office space in Q3, according to a CBRE report, with 12 of the 15 submarkets studied reporting positive absorption. Though suburban asking rents ticked downward from Q2 to Q3, the bulk of the absorption was in Class-A space, meaning that the remaining availability tends to be in cheaper locations.

“Generally speaking, I think now would be a good time for Workspace to [have the IPO], because market fundamentals are good, at least in the Philly suburbs, and we foresee another good year in 2018,” CBRE Research Director Ian Anderson said.

Rather than a reflection of current market conditions, the lack of investor interest that likely gave Workspace cold feet could be more due to certain types of investors "categorically" writing off suburban office as a property type, Anderson said. Pension funds and other REITs with long-term views tend to view urban office as more reliable than suburban.

Workspace had hoped to sell 39 million shares — about 50% of the company — at about $12 to $15 per share, with a goal of raising around $572M. It promised "our current capital structure and balance sheet provides us with sufficient flexibility to grow our brand” in a statement.

The bulk of Workspace's portfolio comes from large portfolio acquisitions from Liberty Property Trust, including 41 properties in Horsham, where Workspace is headquartered. Liberty shed nearly all of its office portfolio in an attempt to focus on core urban properties. Workspace, by contrast, has nearly the entirety of its 9.9M SF portfolio of office and light industrial properties in suburban Pennsylvania, Arizona, Florida and Minnesota.