Exercise of Warrant. This Warrant may be exercised in whole or in part at any time or from time to time but not later than 5.00 P.M., Mountain time, on October 30, 2020, if the Expiration Date is a day on which banking institutions are authorized by law to close, then this Warrant may be exercised on the next succeeding day which shall not be such a day, by presentation and surrender of this Warrant to the Company or at the office of its stock transfer agent, if any, with the Purchase Form annexed hereto duly executed and accompanied by payment of the Exercise Price for the number of Shares of Warrant Stock specified in such form, together with all Federal and state taxes applicable upon such exercise.

Exercise of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company of a duly executed facsimile copy or PDF copy submitted by e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”). Within the earlier of # two (2) Trading Days and # the number of Trading Days comprising the Standard Settlement Period (as defined in Section 2(d)(i) herein) following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise Price for the shares

Exercise of Warrant. Subject to the provisions of [Section 2(e)] herein, exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company of a duly executed facsimile copy or PDF copy submitted by e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”). Within the earlier of # two (2) Trading Days and # the number of Trading Days comprising the Standard Settlement Period (as defined in [Section 2(d)(i)] herein) following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise Price for the shares specified in the applicable Notice of Exercise by wire transfer or cashier’s check drawn on a United States bank unless the cashless exercise procedure specified in [Section 2(c)] below is specified in the applicable Notice of Exercise. No ink-original Notice of Exercise shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization) of any Notice of Exercise be required. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company until the Holder has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation within three (3) Trading Days of the date on which the final Notice of Exercise is delivered to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and

Exercise of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company of a duly executed facsimile copy or PDF copy submitted by e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”). Within the

Exercise of Warrant. Subject to the terms and conditions hereof, upon the announcement by the Company of the occurrence of a Series B Milestone Event and the reduction of the Termination Date to 45 days following the date of such announcement, this Warrant may be exercised for, at the Holder’s discretion, either # Warrant Shares or # in the event that the limitations set forth in Section 2(e) restrict the exercise of this Warrant into Warrant Shares, a Pre-Funded Warrant to purchase a number of shares of Common Stock equal to the number of Warrant Shares as to which this Warrant is being exercised in the form of a Pre-Funded Warrant attached as Exhibit A-11] to the Purchase Agreement. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company of a duly executed PDF copy submitted by e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”). Within the earlier of # two (2) Trading Days and # the number of Trading Days comprising the Standard Settlement Period (as defined in Section 2(d)(i) herein) following the date of exercise as aforesaid, the Holder shall deliver, by wire transfer or cashier’s check drawn on a United States bank unless the cashless exercise procedure specified in Section 2(c) below is specified in the applicable Notice of Exercise, # if this Warrant is being exercised into Warrant Shares, the aggregate Exercise Price for the Warrant Shares specified in the applicable Notice of Exercise or # if this Warrant is being exercised for Pre-Funded Warrants, the aggregate Exercise Price for the Warrant Shares covered by a Pre-Funded Warrant as to which this Warrant is being exercised, as specified in the applicable Notice of Exercise, minus the aggregate Pre-Funded Warrant Exercise Price for such Warrant Shares covered by the Pre-Funded Warrant. No ink-original Notice of Exercise shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization) of any Notice of Exercise be required. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company until the Holder has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation as soon as reasonably practicable following the date on which the final Notice of Exercise is delivered to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and the date of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Trading Day of receipt of such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase hereunder at any given time may be less than the amount stated on the face hereof.

This Warrant may be exercised with respect to Shares, in full or in part at any time or from time to time, for Shares until the Expiration Time by the Holder by surrender of this Warrant and the exercise notice annexed hereto as Exhibit A duly executed by such Holder, to the Company at its principal office, accompanied by payment, in cash, wire transfer of immediately available funds in the amount obtained by multiplying # the number of Shares designated by the holder in the notice of exercise by # the Exercise Price then in effect. On any partial exercise, the Company at its expense will forthwith issue and deliver to or upon the order of the holder hereof a new Warrant or Warrants of like tenor, in the name of the holder hereof or as such holder (upon payment by such holder of any applicable transfer taxes and subject to applicable securities laws) may request, providing in the aggregate on the face or faces thereof for the number of shares, or percentage of equity, as applicable, for which such Warrant or Warrants may still be exercised.

Exercise of Warrant. The purchase rights represented by this Warrant are exercisable by the Holder in whole or in part, at any time, or from time to time, during the term hereof as described in Section 3 above, by the surrender of this Warrant and the Notice of Exercise annexed hereto duly completed and executed on behalf of the Holder, at the principal offices of the Company (or such other office or agency of the Company as it may designate by notice in writing to the Holder), upon payment in cash or by check acceptable to the Company of the Exercise Price of the shares to be purchased.

Exercise of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company of a duly executed facsimile copy or PDF copy submitted by e-mail (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “Notice of Exercise”). Within the earlier of # two (2) Trading Days and # the number of Trading Days comprising the Standard Settlement Period (as defined in Section 2(d)(i) herein) following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise Price for the shares specified in the applicable Notice of Exercise by wire transfer or cashier’s check drawn on a United States bank unless the cashless exercise procedure specified in Section 2(c) below is specified in the applicable Notice of Exercise. No ink-original Notice of Exercise shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization) of any Notice of Exercise be required. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company until the Holder has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation within three (3) Trading Days of the date on which the final Notice of Exercise is delivered to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and the date of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Business Day of receipt of such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase hereunder at any given time may be less than the amount stated on the face hereof.

Exercise of Warrant. Subject to the provisions hereof, this Warrant may be exercised, in whole or in part, or sold, assigned or transferred at any time or from time to time up to four years hereafter. This Warrant shall be exercised by presentation and surrender hereof to OTEC at the principal office of OTEC, accompanied by # a written notice of exercise, # payment to OTEC, for the account of OTEC, of the Exercise Price for the number of shares of Common Stock specified in such notice, and # a certificate of the Holder specifying the event or events, which have occurred and entitle the Holder to exercise this Warrant. The Exercise Price for the number of shares of Common Stock specified in the notice shall be payable in immediately available funds.

Exercise of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company (or such other office or agency of the Company as the Company may designate by notice in writing to the registered Holder at the address of the Holder appearing on the books of the Company) of a duly executed facsimile copy of the Notice of Exercise Form annexed hereto; and, within three (3) Trading Days of the date said Notice of Exercise is delivered to the Company, the Company shall have received payment of the aggregate Exercise Price of the shares thereby purchased by wire transfer or cashier’s check drawn on a United States bank [or, if available, pursuant to the cashless exercise procedure specified in Section 2(c) below]. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company prior to the Termination Date until the Holder has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation within three (3) Trading Days of the date the final Notice of Exercise is delivered to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased