On December 15, 2020, AIR Operating Partnership completed the Separation, which was effected through a pro rata distribution of all of the outstanding common limited partnership units of Aimco Operating Partnership to holders of AIR Operating Partnership common limited partnership units and AIR Operating Partnership Class I High Performance partnership units as of the close of business on December 5, 2020. Stockholders of AIR’s Predecessor received one share of Class A common stock of AIR for every one share of Class A common stock of AIR’s Predecessor held as of the close of business on the record date, and received cash in lieu of fractional shares of Class A common stock of AIR.

At December 31, 2020, AIR Operating Partnership had Class A outstanding preferred units similar to AIR’s Preferred Stock discussed in Note 8. All Class A Partnership Preferred Units are senior to the AIR Operating Partnership common partnership units. Distributions on all Partnership Preferred Units are subject to being declared by the General Partner. The Partnership Preferred Units are redeemable by the AIR Operating Partnership only in connection with a concurrent redemption by AIR of the corresponding AIR Preferred Stock held by unrelated parties.

The AIR Operating Partnership has outstanding various classes of redeemable preferred OP Units. As of December 31, 2020 and 2019, the AIR Operating Partnership had the following classes of preferred OP Units (stated at their redemption values, in thousands, except unit and per unit data):

	Distributions per Annum					Units Issued and Outstanding				Redemption Values
Class of Preferred Units	Percent			Per Unit		2020		2019		2020		2019
Class One		8.75	%	$	8.00		90,000		90,000	$	8,229	$	8,229
Class Two		1.92	%	$	0.48		11,122		11,122		278		278
Class Three		7.88	%	$	1.97		1,313,927		1,338,524		32,848		33,463
Class Four		8.00	%	$	2.00		644,954		644,954		16,124		16,124
Class Six		8.50	%	$	2.13		773,693		773,693		19,342		19,342
Class Seven		7.87	%	$	1.97		26,150		26,150		654		654
Class Nine		6.00	%	$	1.50		78,956		78,956		1,974		1,974
Class Ten		6.00	%	$	1.50		—		680,000		—		17,000
Total							2,938,802		3,643,399	$	79,449	$	97,064

Each class of preferred OP Units is currently redeemable at the holders’ option. The AIR Operating Partnership, at its sole discretion, may settle such redemption requests in cash or cause AIR to issue shares of its Common Stock with a value equal to the redemption price. In the event the AIR Operating Partnership requires AIR to issue shares of Common Stock to settle a redemption request, the AIR Operating Partnership would issue to AIR a corresponding number of common OP Units. The AIR Operating Partnership has a redemption policy that requires cash settlement of redemption requests for the preferred OP Units,

subject to limited exceptions. Subject to certain conditions, the Class Four and Class Six preferred OP Units may be converted into common OP Units.

These redeemable units are classified within temporary equity in AIR’s consolidated balance sheets and within temporary capital in the AIR Operating Partnership’s consolidated balance sheets.

During the years ended December 31, 2020, 2019, and 2018, approximately 705,000, 169,000 and 10,000 preferred OP Units, respectively, were redeemed in exchange for cash, and no preferred OP Units were redeemed in exchange for shares of AIR Common Stock or common OP Units.

The following table presents a reconciliation of the AIR Operating Partnership’s preferred OP Units during the year ended December 31, 2020 (in thousands):

In the AIR Operating Partnership’s consolidated balance sheets, the common partnership units held by AIR are classified within Partners’ Capital as General Partner and Special Limited Partner capital and the common OP Units are classified within Limited Partners’ capital. In AIR’s consolidated balance sheets, the common OP Units are classified within permanent equity as common noncontrolling interests in the AIR Operating Partnership.

Common partnership units held by AIR are not redeemable whereas common OP Units are redeemable at the holders’ option, subject to certain restrictions, on the basis of one common OP Unit for either one share of Common Stock or cash equal to the fair value of a share of Common Stock at the time of redemption. AIR has the option to deliver shares of Common Stock in exchange for all or any portion of the common OP Units tendered for redemption. When a limited partner redeems a common OP Unit for Common Stock, Limited Partners’ capital is reduced and the General Partner and Special Limited Partners’ capital is increased.

During the years ended December 31, 2020, 2019, and 2018, approximately 64,000, 129,000 and 224,000 common OP Units, respectively, were redeemed in exchange for cash. During the years ended December 31, 2020 and 2019, 159,000 and 127,000 common OP Units were redeemed in exchange for shares of Common Stock. No common OP Units were redeemed in exchange for AIR Common Stock during the year ended December 31, 2018.

The holders of the common OP Units receive distributions, prorated from the date of issuance, in an amount equivalent to the dividends paid to holders of Common Stock. During the years ended December 31, 2020, 2019, and 2018, the Aimco Operating Partnership declared regular quarterly distributions per common unit of $0.41, $0.39 and $0.38, respectively, excluding distributions declared as part of the special distribution.

On October 21, 2020, the Board of Directors authorized a reverse unit split and special distribution in the same form and with the same timing as the reverse stock split and special dividend discussed in Note 8 above. The special distribution to the holders of Aimco Operating Partnership common partnership units consisted of $128.7 million in cash and 35.4 million common partnership units. Total common partnership units outstanding prior to and following both transactions was unchanged.

On February 3, 2019, the Board of Directors authorized a reverse unit split and special distribution on the same form and with the same timing as the reverse stock split and special dividend discussed in Note 8 above. The special distribution to the holders of Aimco Operating Partnership common partnership units consisted of $72.7 million in cash, 4.8 million common partnership units and $0.4 million of cash paid in lieu of issuing fractional units. Total common partnership units outstanding prior to and following both transactions was unchanged.