v3.20.1

Warrant plans - Rollforward (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 EquityInstruments € / shares | Dec. 31, 2018 EquityInstruments € / shares | Dec. 31, 2017 EquityInstruments € / shares | Dec. 31, 2016 EquityInstruments € / shares
Warrant plans |  |  |  |
Outstanding at the beginning of the year | EquityInstruments | 4,626,782 | 3,970,807 | 3,466,407 |
Granted during the period | EquityInstruments | 1,699,690 | 1,235,245 | 873,000 |
Forfeited during the year | EquityInstruments | (30,750) | (12,000) |  |
Exercised during the period | EquityInstruments | (754,605) | (567,270) | (368,200) |
Expired during the year | EquityInstruments |  |  | (400) |
Outstanding at the end of the year | EquityInstruments | 5,541,117 | 4,626,782 | 3,970,807 |
Exercisable | EquityInstruments | 1,139,682 | 882,734 | 763,344 | 669,704
Weighted average exercise price at beginning of the year | € / shares | € 53.30 | € 39.32 | € 27.1 |
Granted during the period | € / shares | 95.1 | 79.9 | 77.5 |
Forfeited during the year | € / shares | 88.9 | 43.2 |  |
Exercised during the period | € / shares | 22.8 | 13.5 | 14.4 |
Expired during the year | € / shares |  |  | 19.4 |
Weighted average exercise price at end of the year | € / shares | 70.09 | 53.30 | 39.32 |
Exercisable | € / shares | € 30.2 | € 14.0 | € 13.7 | € 10.3

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