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| 0001558370-18-008331-index.html | 2018-11-02 11:43:58 | |
| 0001558370-18-008331.txt | 2018-11-02 11:43:58 | |
 0001558370-18-008331-xbrl.zip | 208108 | 2018-11-02 11:43:58 |
| FilingSummary.xml | 29959 | 2018-11-02 11:43:58 |
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| imgn-20180930x10q.htm | 1645540 | 2018-11-02 11:43:58 |
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| imgn-20180930_def.xml | 331812 | 2018-11-02 11:43:58 |
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| report.css | 2767 | 2018-11-02 11:43:58 |
| Show.js | 1085 | 2018-11-02 11:43:58 |