Equity	6 Months Ended
Jun. 30, 2013
Equity [Abstract]
Equity	7. Equity Warrants BioTime has issued warrants to purchase its common shares as payments for services and in connection to certain business acquisitions. At June 30, 2013, 1,751,615 warrants to purchase common shares with a weighted average exercise price of $6.59 and a weighted average remaining contractual life of 2.12 years were outstanding. At December 31, 2012, 556,613 warrants to purchase common shares with a weighted average exercise price of $10.00 and a weighted average remaining contractual life of 1.32 years were outstanding. Preferred Shares BioTime is authorized to issue 2,000,000 preferred shares. The shareholders approved the increase in the number of authorized preferred shares from 1,000,000 to 2,000,000 in May 2013. The preferred shares may be issued in one or more series as the board of directors may by resolution determine. The board of directors is authorized to fix the number of shares of any series of preferred shares and to determine or alter the rights, references, privileges, and restrictions granted to or imposed on the preferred shares as a class, or upon any wholly unissued series of any preferred shares. The board of directors may, by resolution, increase or decrease (but not below the number of shares of such series then outstanding) the number of shares of any series of preferred shares subsequent to the issue of shares of that series. As of June 30, 2013 BioTime has no issued and outstanding preferred shares. Common Shares BioTime is authorized to issue 125,000,000 common shares with no par value. The shareholders approved the increase in the number of authorized common shares from 75,000,000 to 125,000,000 in May 2013. As of June 30, 2013, BioTime had issued 57,932,220 common shares and outstanding 55,616,934 common shares. The difference between the issued and outstanding number of common shares reflects the treasury stock treatment, for financial reporting purposes, of BioTime common shares held by its subsidiaries. During the six months ended June 30, 2013, BioTime raised gross proceeds of $11,571,953 from the sale of 2,594,156 BioTime common shares at a weighted average price of $4.46 per share in the open market through our Controlled Equity Offering facility with Cantor Fitzgerald & Co. and through the sale of BioTime shares held by BioTime’s majority owned subsidiaries, LifeMap Sciences and Cell Cure Neurosciences. The proceeds of the sale of BioTime shares by its subsidiaries belong to those subsidiaries. In January 2013, BioTime and a private investor entered into a Stock and Warrant Purchase Agreement under which the investor agreed to invest $5,000,000 in BioTime by purchasing, in two tranches, an aggregate of 1,350,000 BioTime common shares and warrants to purchase approximately 650,000 additional BioTime common shares. The first tranche of $2,000,000 was funded on January 14, 2013, and BioTime issued to the investor 540,000 common shares and 259,999 warrants. BioTime received the second tranche of $3,000,000 on April 10, 2013 at which time BioTime issued to the investor 810,000 common shares, and warrants to purchase an additional 389,999 common shares at an exercise price of $5.00 per share. In June 2013, BioTime sold 2,180,016 common shares and 545,004 warrants to purchase common shares for gross proceeds of $9,057,967 under the Stock and Warrant Purchase Agreement entered between BioTime and certain investors. The common shares and warrants to purchase common shares were sold in "units" with each unit consisting of one common share and one-quarter of a warrant, at an offering price of $4.155 per unit. The warrants have an initial exercise price of $5.00 per share and are exercisable during the three year period beginning on the date of issuance, June 6, 2013. During the six months ended June 30, 2013, no options or warrants were exercised. During the six months ended June 30, 2013 and 2012, BioTime recognized stock-based compensation expenses of $1,351,795 and $929,257, respectively, due to stock options granted to employees and directors. During the six months ended June 30, 2013 and 2012, BioTime granted 1,155,000 and 130,000 options, respectively, under its 2012 Equity Incentive Plan and 2002 Stock Option Plan. Asterias granted 2,700,000 and nil options, respectively under its 2013 Equity Incentive Plan; OrthoCyte granted nil and 300,000 options, respectively under its 2010 Stock Option Plan; OncoCyte granted 80,000 and nil options, respectively under its 2011 Stock Option Plan; ReCyte granted nil and 550,000 options, respectively under its 2011 Stock Option Plan; LifeMap Sciences granted nil and 217,143 options, respectively under its 2011 Stock Option Plan; and BioTime Asia did not grant any options in either periods. Option on LifeMap Sciences Common Stock Held by BioTime As a condition to the sale of BioTime shares and warrants under the terms of a Stock and Warrant Purchase Agreement during June 2013, BioTime entered into an Option Agreement with certain investors. Under the Option Agreement, each investor has an option to purchase a number of shares of common stock that BioTime holds in its subsidiary LifeMap Sciences, initially equal to the number of warrants that the investors purchased from BioTime. The options to purchase shares of LifeMap Sciences common stock may be exercised at a price of $4.00 per share in lieu of exercising the warrants to purchase BioTime common shares. The exercise of an option by an investor will require the cancellation of one BioTime warrant for each share of LifeMap Sciences common stock (as adjusted to reflect any stock dividend, stock split, reverse stock split or other certain other transactions) purchased by the investor, so that an investor will have to choose between purchasing BioTime common shares and LifeMap Sciences common stock when they exercise either the warrants or the options. The right of a holder of an option to exercise its option is subject to the availability of an exemption from registration under the Securities Act of 1933, as amended.

Equity

6 Months Ended

Jun. 30, 2013

7. Equity

Warrants

BioTime has issued warrants to purchase its common shares as payments for services and in connection to certain business acquisitions. At June 30, 2013, 1,751,615 warrants to purchase common shares with a weighted average exercise price of $6.59 and a weighted average remaining contractual life of 2.12 years were outstanding. At December 31, 2012, 556,613 warrants to purchase common shares with a weighted average exercise price of $10.00 and a weighted average remaining contractual life of 1.32 years were outstanding.

Preferred Shares

BioTime is authorized to issue 2,000,000 preferred shares. The shareholders approved the increase in the number of authorized preferred shares from 1,000,000 to 2,000,000 in May 2013. The preferred shares may be issued in one or more series as the board of directors may by resolution determine. The board of directors is authorized to fix the number of shares of any series of preferred shares and to determine or alter the rights, references, privileges, and restrictions granted to or imposed on the preferred shares as a class, or upon any wholly unissued series of any preferred shares. The board of directors may, by resolution, increase or decrease (but not below the number of shares of such series then outstanding) the number of shares of any series of preferred shares subsequent to the issue of shares of that series.

As of June 30, 2013 BioTime has no issued and outstanding preferred shares.

Common Shares

BioTime is authorized to issue 125,000,000 common shares with no par value. The shareholders approved the increase in the number of authorized common shares from 75,000,000 to 125,000,000 in May 2013. As of June 30, 2013, BioTime had issued 57,932,220 common shares and outstanding 55,616,934 common shares. The difference between the issued and outstanding number of common shares reflects the treasury stock treatment, for financial reporting purposes, of BioTime common shares held by its subsidiaries.

During the six months ended June 30, 2013, BioTime raised gross proceeds of $11,571,953 from the sale of 2,594,156 BioTime common shares at a weighted average price of $4.46 per share in the open market through our Controlled Equity Offering facility with Cantor Fitzgerald & Co. and through the sale of BioTime shares held by BioTime’s majority owned subsidiaries, LifeMap Sciences and Cell Cure Neurosciences. The proceeds of the sale of BioTime shares by its subsidiaries belong to those subsidiaries.

In January 2013, BioTime and a private investor entered into a Stock and Warrant Purchase Agreement under which the investor agreed to invest $5,000,000 in BioTime by purchasing, in two tranches, an aggregate of 1,350,000 BioTime common shares and warrants to purchase approximately 650,000 additional BioTime common shares. The first tranche of $2,000,000 was funded on January 14, 2013, and BioTime issued to the investor 540,000 common shares and 259,999 warrants. BioTime received the second tranche of $3,000,000 on April 10, 2013 at which time BioTime issued to the investor 810,000 common shares, and warrants to purchase an additional 389,999 common shares at an exercise price of $5.00 per share.

In June 2013, BioTime sold 2,180,016 common shares and 545,004 warrants to purchase common shares for gross proceeds of $9,057,967 under the Stock and Warrant Purchase Agreement entered between BioTime and certain investors. The common shares and warrants to purchase common shares were sold in "units" with each unit consisting of one common share and one-quarter of a warrant, at an offering price of $4.155 per unit. The warrants have an initial exercise price of $5.00 per share and are exercisable during the three year period beginning on the date of issuance, June 6, 2013.

During the six months ended June 30, 2013, no options or warrants were exercised.

During the six months ended June 30, 2013 and 2012, BioTime recognized stock-based compensation expenses of $1,351,795 and $929,257, respectively, due to stock options granted to employees and directors. During the six months ended June 30, 2013 and 2012, BioTime granted 1,155,000 and 130,000 options, respectively, under its 2012 Equity Incentive Plan and 2002 Stock Option Plan. Asterias granted 2,700,000 and nil options, respectively under its 2013 Equity Incentive Plan; OrthoCyte granted nil and 300,000 options, respectively under its 2010 Stock Option Plan; OncoCyte granted 80,000 and nil options, respectively under its 2011 Stock Option Plan; ReCyte granted nil and 550,000 options, respectively under its 2011 Stock Option Plan; LifeMap Sciences granted nil and 217,143 options, respectively under its 2011 Stock Option Plan; and BioTime Asia did not grant any options in either periods.

Option on LifeMap Sciences Common Stock Held by BioTime

As a condition to the sale of BioTime shares and warrants under the terms of a Stock and Warrant Purchase Agreement during June 2013, BioTime entered into an Option Agreement with certain investors. Under the Option Agreement, each investor has an option to purchase a number of shares of common stock that BioTime holds in its subsidiary LifeMap Sciences, initially equal to the number of warrants that the investors purchased from BioTime. The options to purchase shares of LifeMap Sciences common stock may be exercised at a price of $4.00 per share in lieu of exercising the warrants to purchase BioTime common shares. The exercise of an option by an investor will require the cancellation of one BioTime warrant for each share of LifeMap Sciences common stock (as adjusted to reflect any stock dividend, stock split, reverse stock split or other certain other transactions) purchased by the investor, so that an investor will have to choose between purchasing BioTime common shares and LifeMap Sciences common stock when they exercise either the warrants or the options. The right of a holder of an option to exercise its option is subject to the availability of an exemption from registration under the Securities Act of 1933, as amended.