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Share-based Payment Arrangement (Tables) | 12 Months Ended
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Dec. 31, 2020
Senao International Co., Ltd. (SENAO) [Member] |
Statement [LineItems] |
Share-based Compensation Plan |
| a. | SENAO share-based compensation plan (“SENAO Plan”) described as follows:
Effective Date |  | Grant Date |  | Stock Options Units |  |  | Exercise Price
|  |  |  | (In Thousands) |  |  | NT$
2012.05.28 |  | 2013.05.07 |  |  | 10,000 |  |  | $66.20 (Original price$93.00)
Outstanding Stock Options | Information about SENAO’s outstanding stock options for the years ended December 31, 2018 and 2019 was as follows:
|  | Year Ended December 31, 2018 |
|  | Granted on May 7, 2013 |
|  | Number of Options |  |  | Weighted- average Exercise Price |
|  | (In Thousands) |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 5,926 |  |  | $ | 70.70 |
Options forfeited |  |  | (608 | ) |  |  | — |
Options outstanding at end of the year |  |  | 5,318 |  |  |  | 66.20 |
Options exercisable at end of the year |  |  | 5,318 |  |  |  | 66.20 |
|  | Year Ended December 31, 2019 |
|  | Granted on May 7, 2013 |
|  | Number of Options |  |  | Weighted- average Exercise Price |
|  | (In Thousands) |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 5,318 |  |  | $ | 66.20 |
Options forfeited |  |  | (5,318 | ) |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |
Options exercisable at end of the year |  |  | — |  |  |  | — |
Assumptions used to Evaluate Options and Fair Value of Options | SENAO used the fair value method to evaluate the options using the Black-Scholes model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted on May 7, 2013 |
Grant-date share price (NT$) |  | $ | 93.00 |
Exercise price (NT$) |  | $ | 93.00 |
Dividend yield |  |  | — |
Risk-free interest rate |  |  | 0.91 | %
Expected life |  | 4.375 years |
Expected volatility |  |  | 36.22 | %
Weighted average fair value of grants (NT$) |  | $ | 28.72 |
SENAO used the fair value method to evaluate share-based payment transaction using the Black-Scholes model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted on May 7, 2018 |
Grant-date share price (NT$) |  | $ | 51.60 |
Exercise price (NT$) |  | $ | 49.28 |
Dividend yield |  |  | — |
Risk-free interest rate |  |  | 0.59 | %
Expected life |  | 18 days |
Expected volatility |  |  | 8.78 | %
Weighted average fair value of grants (NT$) |  | $ | 2.34 |
Share-based Compensation Plan |
| a. | SENAO share-based compensation plan (“SENAO Plan”) described as follows:
Effective Date |  | Grant Date |  | Stock Options Units |  |  | Exercise Price
|  |  |  | (In Thousands) |  |  | NT$
2012.05.28 |  | 2013.05.07 |  |  | 10,000 |  |  | $66.20 (Original price$93.00)
Outstanding Stock Options | Information about SENAO’s outstanding stock options for the years ended December 31, 2018 and 2019 was as follows:
|  | Year Ended December 31, 2018 |
|  | Granted on May 7, 2013 |
|  | Number of Options |  |  | Weighted- average Exercise Price |
|  | (In Thousands) |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 5,926 |  |  | $ | 70.70 |
Options forfeited |  |  | (608 | ) |  |  | — |
Options outstanding at end of the year |  |  | 5,318 |  |  |  | 66.20 |
Options exercisable at end of the year |  |  | 5,318 |  |  |  | 66.20 |
|  | Year Ended December 31, 2019 |
|  | Granted on May 7, 2013 |
|  | Number of Options |  |  | Weighted- average Exercise Price |
|  | (In Thousands) |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 5,318 |  |  | $ | 66.20 |
Options forfeited |  |  | (5,318 | ) |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |
Options exercisable at end of the year |  |  | — |  |  |  | — |
CHIEF Telecom Inc. (CHIEF) [Member] |
Statement [LineItems] |
Share-based Compensation Plan |
| c. | CHIEF share-based compensation plan (“CHIEF Plan”) described as follows:
Effective Date |  | Grant Date |  | Stock Options Units |  |  | Exercise Price
|  |  |  |  |  |  |  | NT$
2015.11.17 |  | 2015.10.22 |  |  | 2,000.00 |  |  | $34.40 (Original price$43.00)
2017.12.18 |  | 2017.12.19 |  |  | 950.00 |  |  | $132.70 (Original price$147.00)
|  | 2018.10.31 |  |  | 50.00 |  |  | $138.70 (Original price$147.00)
2020.09.16 |  | 2020.11.13 |  |  | 200.00 |  |  | $206.00
Outstanding Stock Options | Information about CHIEF’s outstanding stock options for the years ended December 31, 2018, 2019 and 2020 was as follows:
|  | Year Ended December 31, 2018 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 1,936.00 |  |  | $ | 34.40 |  |  |  | 950.00 |  |  | $ | 147.00 |  |  |  | — |  |  | $ | — |
Options granted |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 50.00 |  |  |  | 147.00 |
Options exercised |  |  | (1,027.25 | ) |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Options forfeited |  |  | (26.00 | ) |  |  | — |  |  |  | (25.00 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | 882.75 |  |  |  | 34.40 |  |  |  | 925.00 |  |  |  | 140.60 |  |  |  | 50.00 |  |  |  | 147.00 |
Options exercisable at end of the year |  |  | 416.50 |  |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
|  | Year Ended December 31, 2019 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 882.75 |  |  | $ | 34.40 |  |  |  | 925.00 |  |  | $ | 140.60 |  |  |  | 50.00 |  |  | $ | 147.00 |
Options exercised |  |  | (547.25 | ) |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Options forfeited |  |  | (21.25 | ) |  |  | — |  |  |  | (28.00 | ) |  |  | — |  |  |  | (4.00 | ) |  |  | — |
Options outstanding at end of the year |  |  | 314.25 |  |  |  | 34.40 |  |  |  | 897.00 |  |  |  | 135.60 |  |  |  | 46.00 |  |  |  | 141.70 |
Options exercisable at end of the year |  |  | 314.25 |  |  |  | 34.40 |  |  |  | 448.50 |  |  |  | 135.60 |  |  |  | — |  |  |  | — |
|  | Year Ended December 31, 2020 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |  |  | Granted on November 13, 2020 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 314.25 |  |  | $ | 34.40 |  |  |  | 897.00 |  |  | $ | 135.60 |  |  |  | 46.00 |  |  | $ | 141.70 |  |  |  | — |  |  | $ | — |
Options granted |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 200 |  |  |  | 206.00 |
Options exercised |  |  | (314.25 | ) |  |  | 34.40 |  |  |  | (448.50 | ) |  |  | 135.60 |  |  |  | (21.00 | ) |  |  | 138.70 |  |  |  | — |  |  |  | — |
Options forfeited |  |  | — |  |  |  | — |  |  |  | (21.00 | ) |  |  | — |  |  |  | (4.00 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |  |  |  | 427.50 |  |  |  | 132.70 |  |  |  | 21.00 |  |  |  | 138.70 |  |  |  | 200.00 |  |  |  | 206.00 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  |  | 213.75 |  |  |  | 132.70 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee Stock Options Outstanding | As of December 31, 2019, information about employee stock options outstanding was as follows:
Granted on October 22, 2015 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 34.40 |  |  |  | 314.25 |  |  |  | 0.81 |  |  | $ | 34.40 |  |  |  | 314.25 |  |  | $ | 34.40 |
Granted on December 19, 2017 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 135.60 |  |  |  | 897.00 |  |  |  | 2.96 |  |  | $ | 135.60 |  |  |  | 448.50 |  |  | $ | 135.60 |
Granted on October 31, 2018 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 141.70 |  |  |  | 46.00 |  |  |  | 3.83 |  |  | $ | 141.70 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, information about employee stock options outstanding was as follows:
Granted on December 19, 2017 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 132.70 |  |  |  | 427.50 |  |  |  | 1.96 |  |  | $ | 132.70 |  |  |  | 213.75 |  |  | $ | 132.70 |
Granted on October 31, 2018 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 138.70 |  |  |  | 21.00 |  |  |  | 2.83 |  |  | $ | 138.70 |  |  |  | — |  |  | $ | — |
Granted on November 13, 2020 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 206.00 |  |  |  | 200.00 |  |  |  | 4.87 |  |  | $ | 206.00 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, all the stock options granted on October 22, 2015 were exercised or forfeited.
Assumptions used to Evaluate Options and Fair Value of Options | CHIEF used the fair value method to evaluate the options using the Black-Scholes model and binomial option pricing model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted on October 22, 2015 |  |  | Stock Options Granted on December 19, 2017 |  |  | Stock Options Granted on October 31, 2018 |  |  | Stock Options Granted on November 13, 2020 |
Grant-date share price (NT$) |  | $ | 39.55 |  |  | $ | 95.92 |  |  | $ | 166.00 |  |  | $ | 356.00 |
Exercise price (NT$) |  | $ | 43.00 |  |  | $ | 147.00 |  |  | $ | 147.00 |  |  | $ | 206.00 |
Dividend yield |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Risk-free interest rate |  |  | 0.86 | % |  |  | 0.62 | % |  |  | 0.72 | % |  |  | 0.18 | %
Expected life |  | 5 years |  |  | 5 years |  |  | 5 years |  |  | 5 years |
Expected volatility |  |  | 21.02 | % |  |  | 17.35 | % |  |  | 16.60 | % |  |  | 34.61 | %
Weighted average fair value of grants (NT$) |  | $ | 4,863 |  |  | $ | 2,318 |  |  | $ | 33,540 |  |  | $ | 173,893 |
CHIEF used the fair value method to evaluate the options granted to employees on May 22, 2018 using the Black-Scholes model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted on May 22, 2018 |
Grant-date share price (NT$) |  | $ | 156.41 |
Exercise price (NT$) |  | $ | 170.00 |
Dividend yield |  |  | — |
Risk-free interest rate |  |  | 0.34 | %
Expected life |  | 7 days |
Expected volatility |  |  | 14.33 | %
Weighted average fair value of grants (NT$) |  | $ | — |
Share-based Compensation Plan |
| c. | CHIEF share-based compensation plan (“CHIEF Plan”) described as follows:
Effective Date |  | Grant Date |  | Stock Options Units |  |  | Exercise Price
|  |  |  |  |  |  |  | NT$
2015.11.17 |  | 2015.10.22 |  |  | 2,000.00 |  |  | $34.40 (Original price$43.00)
2017.12.18 |  | 2017.12.19 |  |  | 950.00 |  |  | $132.70 (Original price$147.00)
|  | 2018.10.31 |  |  | 50.00 |  |  | $138.70 (Original price$147.00)
2020.09.16 |  | 2020.11.13 |  |  | 200.00 |  |  | $206.00
Outstanding Stock Options | Information about CHIEF’s outstanding stock options for the years ended December 31, 2018, 2019 and 2020 was as follows:
|  | Year Ended December 31, 2018 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 1,936.00 |  |  | $ | 34.40 |  |  |  | 950.00 |  |  | $ | 147.00 |  |  |  | — |  |  | $ | — |
Options granted |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 50.00 |  |  |  | 147.00 |
Options exercised |  |  | (1,027.25 | ) |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Options forfeited |  |  | (26.00 | ) |  |  | — |  |  |  | (25.00 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | 882.75 |  |  |  | 34.40 |  |  |  | 925.00 |  |  |  | 140.60 |  |  |  | 50.00 |  |  |  | 147.00 |
Options exercisable at end of the year |  |  | 416.50 |  |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
|  | Year Ended December 31, 2019 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 882.75 |  |  | $ | 34.40 |  |  |  | 925.00 |  |  | $ | 140.60 |  |  |  | 50.00 |  |  | $ | 147.00 |
Options exercised |  |  | (547.25 | ) |  |  | 34.40 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Options forfeited |  |  | (21.25 | ) |  |  | — |  |  |  | (28.00 | ) |  |  | — |  |  |  | (4.00 | ) |  |  | — |
Options outstanding at end of the year |  |  | 314.25 |  |  |  | 34.40 |  |  |  | 897.00 |  |  |  | 135.60 |  |  |  | 46.00 |  |  |  | 141.70 |
Options exercisable at end of the year |  |  | 314.25 |  |  |  | 34.40 |  |  |  | 448.50 |  |  |  | 135.60 |  |  |  | — |  |  |  | — |
|  | Year Ended December 31, 2020 |
|  | Granted on October 22, 2015 |  |  | Granted on December 19, 2017 |  |  | Granted on October 31, 2018 |  |  | Granted on November 13, 2020 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | 314.25 |  |  | $ | 34.40 |  |  |  | 897.00 |  |  | $ | 135.60 |  |  |  | 46.00 |  |  | $ | 141.70 |  |  |  | — |  |  | $ | — |
Options granted |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 200 |  |  |  | 206.00 |
Options exercised |  |  | (314.25 | ) |  |  | 34.40 |  |  |  | (448.50 | ) |  |  | 135.60 |  |  |  | (21.00 | ) |  |  | 138.70 |  |  |  | — |  |  |  | — |
Options forfeited |  |  | — |  |  |  | — |  |  |  | (21.00 | ) |  |  | — |  |  |  | (4.00 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |  |  |  | 427.50 |  |  |  | 132.70 |  |  |  | 21.00 |  |  |  | 138.70 |  |  |  | 200.00 |  |  |  | 206.00 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  |  | 213.75 |  |  |  | 132.70 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee Stock Options Outstanding | As of December 31, 2019, information about employee stock options outstanding was as follows:
Granted on October 22, 2015 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 34.40 |  |  |  | 314.25 |  |  |  | 0.81 |  |  | $ | 34.40 |  |  |  | 314.25 |  |  | $ | 34.40 |
Granted on December 19, 2017 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 135.60 |  |  |  | 897.00 |  |  |  | 2.96 |  |  | $ | 135.60 |  |  |  | 448.50 |  |  | $ | 135.60 |
Granted on October 31, 2018 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 141.70 |  |  |  | 46.00 |  |  |  | 3.83 |  |  | $ | 141.70 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, information about employee stock options outstanding was as follows:
Granted on December 19, 2017 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 132.70 |  |  |  | 427.50 |  |  |  | 1.96 |  |  | $ | 132.70 |  |  |  | 213.75 |  |  | $ | 132.70 |
Granted on October 31, 2018 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 138.70 |  |  |  | 21.00 |  |  |  | 2.83 |  |  | $ | 138.70 |  |  |  | — |  |  | $ | — |
Granted on November 13, 2020 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 206.00 |  |  |  | 200.00 |  |  |  | 4.87 |  |  | $ | 206.00 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, all the stock options granted on October 22, 2015 were exercised or forfeited.
CHT Security Co., Ltd. (CHTSC) [Member] |
Statement [LineItems] |
Outstanding Stock Options | Information about CHTSC’s outstanding stock options for the years ended December 31, 2019 and 2020 was as follows:
|  | Year Ended December 31, |
|  | 2019 |  | 2020 |
|  | Granted on December 20, 2019 |  | Granted on December 20, 2019 |
|  | Number of Options |  |  | Weighted- average Exercise Price |  | Number of Options |  |  | Weighted- average Exercise Price |
|  |  |  |  |  | NT$ |  |  |  |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | — |  |  | $ | — |  |  | 4,500 |  |  | $ | 19.085 |
Options granted |  |  | 4,500 |  |  |  | 19.085 |  |  | — |  |  |  | — |
Options forfeited |  |  | — |  |  |  | — |  |  | (172 | ) |  |  | — |
Options outstanding at end of the year |  |  | 4,500 |  |  |  | 19.085 |  |  | 4,328 |  |  |  | 19.085 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  | 1,082 |  |  |  | 19.085 |
Employee Stock Options Outstanding | As of December 31, 2019, information about employee stock options outstanding was as follows:
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 19.085 |  |  |  | 4,500 |  |  |  | 4.97 |  |  | $ | 19.085 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, information about employee stock options outstanding was as follows:
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 19.085 |  |  |  | 4,328 |  |  |  | 3.97 |  |  | $ | 19.085 |  |  |  | 1,082 |  |  | $ | 19.085 |
Assumptions used to Evaluate Options and Fair Value of Options | CHTSC used the fair value method to evaluate the options using the Black-Scholes model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted on December 20, 2019 |
Grant-date share price (NT$) |  | $ | 20.17 |
Exercise price (NT$) |  | $ | 19.085 |
Dividend yield |  |  | 12.49 | %
Risk-free interest rate |  |  | 0.54 | %
Expected life |  | 5 years |
Expected volatility |  |  | 42.41 | %
Weighted average fair value of grants (NT$) |  | $ | 2,470 |
Outstanding Stock Options | Information about CHTSC’s outstanding stock options for the years ended December 31, 2019 and 2020 was as follows:
|  | Year Ended December 31, |
|  | 2019 |  | 2020 |
|  | Granted on December 20, 2019 |  | Granted on December 20, 2019 |
|  | Number of Options |  |  | Weighted- average Exercise Price |  | Number of Options |  |  | Weighted- average Exercise Price |
|  |  |  |  |  | NT$ |  |  |  |  |  | NT$ |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | — |  |  | $ | — |  |  | 4,500 |  |  | $ | 19.085 |
Options granted |  |  | 4,500 |  |  |  | 19.085 |  |  | — |  |  |  | — |
Options forfeited |  |  | — |  |  |  | — |  |  | (172 | ) |  |  | — |
Options outstanding at end of the year |  |  | 4,500 |  |  |  | 19.085 |  |  | 4,328 |  |  |  | 19.085 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  | 1,082 |  |  |  | 19.085 |
Employee Stock Options Outstanding | As of December 31, 2019, information about employee stock options outstanding was as follows:
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 19.085 |  |  |  | 4,500 |  |  |  | 4.97 |  |  | $ | 19.085 |  |  |  | — |  |  | $ | — |
As of December 31, 2020, information about employee stock options outstanding was as follows:
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 19.085 |  |  |  | 4,328 |  |  |  | 3.97 |  |  | $ | 19.085 |  |  |  | 1,082 |  |  | $ | 19.085 |
IISI Plan [Member] |
Statement [LineItems] |
Outstanding Stock Options | Information about IISI’s outstanding stock options for the year ended December 31, 2020 was as follows:
|  | Year Ended December 31, 2020 |
|  | Granted in August 2013 |  |  | Granted in January 2014 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | — |  |  | $ | — |  |  |  | — |  |  | $ | — |
Options outstanding upon the date of business combination |  |  | 1,022.96 |  |  |  | 14.00 |  |  |  | 580.00 |  |  |  | 14.00 |
Options exercised |  |  | (432.50 | ) |  |  | 14.00 |  |  |  | (50.00 | ) |  |  | 14.00 |
Options forfeited |  |  | (590.46 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |  |  |  | 530.00 |  |  |  | 14.00 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  |  | 530.00 |  |  |  | 14.00 |
Employee Stock Options Outstanding | As of December 31, 2020, information about employee stock options outstanding was as follows:
Granted in January 2014 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 14.00 |  |  |  | 530.00 |  |  |  | 0.04 |  |  | $ | 14.00 |  |  |  | 530.00 |  |  | $ | 14.00 |
Assumptions used to Evaluate Options and Fair Value of Options | IISI used the fair value method to evaluate the options using the Black-Scholes model and the related assumptions and the fair value of the options were as follows:
|  | Stock Options Granted in August 2013 |  |  | Stock Options Granted in January 2014 |
Grant-date share price (NT$) |  | $ | 12.51 |  |  | $ | 14.51 |
Exercise price (NT$) |  | $ | 14.00 |  |  | $ | 14.00 |
Dividend yield |  |  | 6 | % |  |  | 6 | %
Risk-free interest rate |  | 1.20%-1.39% |  |  | 1.16%-1.32% |
Expected life |  | 4.5-5.5 years |  |  | 4.5-5.5 years |
Expected volatility |  | 36.01%-36.62% |  |  | 35.28%-35.97% |
Weighted average fair value of grants (NT$) |  | $ | 12.51 |  |  | $ | 14.51 |
Outstanding Stock Options | Information about IISI’s outstanding stock options for the year ended December 31, 2020 was as follows:
|  | Year Ended December 31, 2020 |
|  | Granted in August 2013 |  |  | Granted in January 2014 |
|  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |  |  | Number of Options |  |  | Weighted Average Exercise Price (NT$) |
Employee stock options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of the year |  |  | — |  |  | $ | — |  |  |  | — |  |  | $ | — |
Options outstanding upon the date of business combination |  |  | 1,022.96 |  |  |  | 14.00 |  |  |  | 580.00 |  |  |  | 14.00 |
Options exercised |  |  | (432.50 | ) |  |  | 14.00 |  |  |  | (50.00 | ) |  |  | 14.00 |
Options forfeited |  |  | (590.46 | ) |  |  | — |  |  |  | — |  |  |  | — |
Options outstanding at end of the year |  |  | — |  |  |  | — |  |  |  | 530.00 |  |  |  | 14.00 |
Options exercisable at end of the year |  |  | — |  |  |  | — |  |  |  | 530.00 |  |  |  | 14.00 |
Employee Stock Options Outstanding | As of December 31, 2020, information about employee stock options outstanding was as follows:
Granted in January 2014 |
Options Outstanding |  |  | Options Exercisable |
Range of Exercise Price |  |  | Number of Options |  |  | Weighted Average Remaining Contractual Life |  |  | Weighted Average Exercise Price |  |  | Number of Options |  |  | Weighted Average Exercise Price |
NT$ |  |  |  |  |  |  | (Years) |  |  | NT$ |  |  |  |  |  |  | NT$ |
$ | 14.00 |  |  |  | 530.00 |  |  |  | 0.04 |  |  | $ | 14.00 |  |  |  | 530.00 |  |  | $ | 14.00 |

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