Exhibit 4.9
​
DESCRIPTION OF COMMON STOCK
​
The following description of our common stock, certain provisions of our articles of incorporation and bylaws, and certain provisions of Washington law are summaries. The following description is not complete and is subject to and qualified in its entirety by our articles of incorporation and bylaws.
​
As of March 15, 2020, our articles of incorporation authorize us to issue 217,000,000 shares of common stock, par value $0.01 per share, and 10,000,000 shares of preferred stock, par value $0.01 per share.
​
Common Stock
​
The holders of our common stock are entitled to the following rights:
​
Voting
​
Our common stock is entitled to one vote for each share held on all matters submitted to a vote of the stockholders, including the election of directors, and does not have cumulative voting rights. Accordingly, the holders of a majority of the shares of our common stock entitled to vote in any election of directors can elect all of the directors standing for election.
​
Dividends
​
Subject to preferences that may be applicable to any then-outstanding preferred stock, the holders of common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds.
​
Liquidation
​
In the event of our liquidation, dissolution or winding-up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.
​
Rights and Preferences
​
Holders of our common stock have no preemptive, conversion or subscription rights, and there is no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that are outstanding or that we may designate and issue in the future.
​
Anti-Takeover Effects of Provisions of Our Articles of Incorporation, Our Bylaws and Washington Law
​
Provisions in our articles of incorporation, our bylaws and under Washington law may delay or prevent an acquisition of us or a change in our management, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. These provisions include a requirement for the vote of stockholders holding at least two-thirds of all shares of our issued and outstanding capital stock to approve certain changes to our articles of incorporation or certain business combinations. These provisions may frustrate or prevent any attempts by our stockholders to replace or remove our current management by making it difficult for stockholders to replace members of our board of directors, which is responsible for appointing the members of our management. Additionally, because we are incorporated in Washington, we are governed by the provisions of Chapter 23B.19 of the Washington Business Corporation Act, which, among other things, prohibits a target corporation, with certain exceptions, from engaging
​



in certain “significant business transactions” for a period of five years after the share acquisition by an “acquiring person”, unless (a) the significant business transaction is approved by a majority of the members of the target corporation’s board of directors prior to the time of acquisition or (b) the significant business transaction was approved by both the majority of the members of the target corporation’s board of directors and approved at a stockholder meeting by at least two-thirds of the outstanding voting shares (excluding the acquiring person’s shares or shares over which the acquiring person has voting control) at or subsequent to the acquiring person’s share acquisition. An “acquiring person” is defined as a person or group of persons which beneficially owns 10% or more of the voting securities of the target corporation. Such significant business transactions may include, among other things:
​
		●	any merger or consolidation with, disposition of assets to, or issuance or redemption of stock to or from, the acquiring person;

​
​
		●	any termination of 5% or more of the employees of the target corporation as a result of the acquiring person’s acquisition of 10% or more of the shares; or

​
​
		●	allowing the acquiring person to receive any disproportionate benefit as a stockholder.

​
​
After the five-year period, a significant business transaction may take place as long as it complies with certain fair price provisions of the statute or is approved by a majority of the votes entitled to be counted within each voting group entitled to vote separately on the transaction (excluding the acquiring person’s shares or shares over which the acquiring person has voting control) at an annual or special meeting of stockholders.
​
NYSE American Listing
​
Our common stock is listed on the NYSE American exchange under the symbol “ARMP.”
​
Transfer Agent and Registrar
​
The transfer agent and registrar for our common stock is Computershare Trust Company, N.A. The transfer agent and registrar’s address is 250 Royall Street, Canton, MA 02021.