Annual report pursuant to Section 13 and 15(d)

Stockholders' equity (Tables)

v3.19.1
Stockholders' equity (Tables) - Tecogen
 12 Months Ended
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Schedule of Stock Option Activity
Stock option activity for the year ended December 31, 2018 was as follows:
Common Stock Options
Number of
Options
 
Exercise
Price
Per
Share
 
Weighted
Average
Exercise
Price
 
Weighted
Average
Remaining
Life
 
Aggregate
Intrinsic
Value
Outstanding, December 31, 2017
1,061,552

 
$0.79-$18.15
 
$
3.60

 
4.95 years
 
$
291,449

Granted
367,500

 
$2.30-$4.04
 
3.35

 
 
 
 

Exercised
(57,854
)
 
$1.20-$2.60
 
1.26

 
 
 
137,085

Canceled and forfeited
(78,609
)
 
$2.30-$18.15
 
6.43

 
 
 
 

Outstanding, December 31, 2018
1,292,589

 
$0.79-$10.33
 
$
3.52

 
5.93 years
 
$
671,331

Exercisable, December 31, 2018
855,089

 
 
 
$
3.46

 
 
 
$
620,266

Vested and expected to vest, December 31, 2018
1,226,964

 
 
 
$
3.51

 
 
 
$
663,672

Summary of Weighted Average Assumptions Used in Black-Scholes Option Pricing
The weighted average assumptions used in the Black-Scholes option pricing model for options granted in 2018 and 2017 are as follows:
Stock option awards:
 
2018
 
2017
Expected life
 
6.25 years
 
6.25 years
Risk-free interest rate
 
2.73%
 
1.86%
Expected volatility
 
20.90%
 
23.10%
Schedule of Restricted Stock Activity
Restricted stock activity for the year ended December 31, 2018 was as follows: 
 
Number of
Restricted
Stock
 
Weighted
Average
Grant Date
Fair Value
Unvested, December 31, 2017
42,921

 
$
1.31

Granted
—

 
—

Vested
(42,921
)
 
1.31

Forfeited
—

 
—

Unvested, December 31, 2018
—

 
$
—