Subsequent events	9 Months Ended
Sep. 30, 2019
Subsequent events
Subsequent events	12. Subsequent events The Company evaluated subsequent events through the time of the filing of this report on Form 10‑Q. Other than as disclosed in these condensed consolidated financial statements, the Company is not aware of any significant events that occurred subsequent to the balance sheet date but prior to the filing of this report that would have a material impact on its condensed consolidated financial statements. Acquisition of 51% interest in PERC Water Corporation On October 24, 2019 (the “Closing Date”), the Company, through its wholly-owned subsidiary, CW-Holdings, entered into a stock purchase agreement (the “Purchase Agreement”) with PERC Water Corporation (“PERC”) and its seven shareholders (collectively, the “Sellers”). Pursuant to the terms of the Purchase Agreement, CW-Holdings purchased a 51% ownership interest in PERC for an aggregate purchase price of approximately $4.1 million in cash. After giving effect to the transactions contemplated by the Purchase Agreement, CW-Holdings owns 51% of the outstanding capital stock of PERC, and four other individuals (the “Remaining Shareholders”), three of whom are PERC executives, own 49% of the outstanding capital stock of PERC. CW-Holdings also acquired from the Remaining Shareholders an option to compel the Remaining Shareholders to sell, and granted to the Remaining Shareholders an option to require CW-Holdings to purchase, the Remaining Shareholders’ 49% ownership interest in PERC at a price based upon the fair market value of PERC at the time of the exercise of the option. CW-Holdings’ option is exercisable on or after the third anniversary of the Closing Date and the Remaining Shareholders’ option is exercisable on or after the fifth anniversary of the Closing Date. PERC is a water infrastructure company headquartered in Cosa Mesa, California that develops, designs, builds, operates and manages wastewater and water reuse infrastructure. PERC generated approximately $8.7 million and $11.8 million in revenue for the nine months ended June 30, 2019 and the twelve months ended September 30, 2018, respectively. In connection with the Purchase Agreement, CW-Holdings and the Remaining Shareholders entered into a shareholders’ agreement, pursuant to which CW-Holdings and the Remaining Shareholders agreed to certain rights and obligations with respect to the governance of PERC. Purchase of land from related party In October 2019, Aerex purchased for $126,500 approximately 1.3 acres of land adjacent to its manufacturing facility from a company owned by the minority shareholder of Aerex.

12. Subsequent events

The Company evaluated subsequent events through the time of the filing of this report on Form 10‑Q. Other than as disclosed in these condensed consolidated financial statements, the Company is not aware of any significant events that occurred subsequent to the balance sheet date but prior to the filing of this report that would have a material impact on its condensed consolidated financial statements.

Acquisition of 51% interest in PERC Water Corporation

On October 24, 2019 (the “Closing Date”), the Company, through its wholly-owned subsidiary, CW-Holdings, entered into a stock purchase agreement (the “Purchase Agreement”) with PERC Water Corporation (“PERC”) and its seven shareholders (collectively, the “Sellers”). Pursuant to the terms of the Purchase Agreement, CW-Holdings purchased a 51% ownership interest in PERC for an aggregate purchase price of approximately $4.1 million in cash. After giving effect to the transactions contemplated by the Purchase Agreement, CW-Holdings owns 51% of the outstanding capital stock of PERC, and four other individuals (the “Remaining Shareholders”), three of whom are PERC executives, own 49% of the outstanding capital stock of PERC.

CW-Holdings also acquired from the Remaining Shareholders an option to compel the Remaining Shareholders to sell, and granted to the Remaining Shareholders an option to require CW-Holdings to purchase, the Remaining Shareholders’ 49% ownership interest in PERC at a price based upon the fair market value of PERC at the time of the exercise of the option. CW-Holdings’ option is exercisable on or after the third anniversary of the Closing Date and the Remaining Shareholders’ option is exercisable on or after the fifth anniversary of the Closing Date.

PERC is a water infrastructure company headquartered in Cosa Mesa, California that develops, designs, builds, operates and manages wastewater and water reuse infrastructure. PERC generated approximately $8.7 million and $11.8 million in revenue for the nine months ended June 30, 2019 and the twelve months ended September 30, 2018, respectively.

In connection with the Purchase Agreement, CW-Holdings and the Remaining Shareholders entered into a shareholders’ agreement, pursuant to which CW-Holdings and the Remaining Shareholders agreed to certain rights and obligations with respect to the governance of PERC.

Purchase of land from related party

In October 2019, Aerex purchased for $126,500 approximately 1.3 acres of land adjacent to its manufacturing facility from a company owned by the minority shareholder of Aerex.