QUINCY — H5 Data Centers is challenging its 2018 tax assessment, claiming Grant County overvalued the property by more than $80 million.

“The Grant County Assessor appraised the subject property on an erroneous basis, resulting in a taxable assessed value that exceeded the subject property’s market value on Jan. 1, 2017,” Garvey Barer, H5’s Seattle-based attorney, wrote in a filing last month with the Douglas County Superior Court.

For 2018, the Grant County Assessor’s office valued H5’s Quincy data center at $116.7 million. However, Denver-based H5 Data Centers, which owns a number of data centers across the country, paid $36.1 million to acquire the property from Quincy Data Centers in July 2018.

H5 contends that purchase price, and not Grant County’s assessment, reflects the real value of the data center. The company is demanding a $450,000 refund on its $1.3 million 2018 property tax bill.

“Grant County’s action in collecting taxes based upon the illegal, erroneous and excessive assessments violates the property tax provisions (of Washington state law),” H5 Data Centers asserts in its complaint, “and the equal protection requirements of the Washington and United States constitutions.”

However, H5 paid the 2018 tax bill in full “under protest,” the filing said. While the typical procedure for contesting assessed value involves filing an appeal with the county Board of Equalization, state law also allows for taxes to be paid under protest, which gives the taxpayer the opportunity to sue in state court for a refund, according to the state Department of Revenue.

H5 Data Centers did not respond to requests for comment.

According to Grant County Prosecuting Attorney Garth Dano, the case was likely filed in Douglas County to ensure that Grant County jurors would not have to hear the case should it go to trial.

“The taxpayers of the county would be hearing the case,” Dano said. “They would have a vested interest.”

Under state law, lawsuits against counties in Washington can be brought in neighboring counties.

According to records available from the Grant County Assessor’s office, the H5 Data Center was valued at $81.3 million for 2019, down from $116.7 million in 2018. The Grant County Assessor valued the property in question at $129.8 million in 2017, $133.5 million in 2016, and $132 million in 2015, the last year for which the Assessor’s Office has records online.

In 2018, H5 was the seventh-largest property tax payer in Grant County. This year they are the eighth-largest.