- All sections
- D - Textilespaper
- D21C - Production of cellulose by removing non-cellulose substances from cellulose- containing materialsregeneration of pulping liquorsapparatus therefor
- D21C 3/04 - Pulping cellulose-containing materials with acids, acid salts, or acid anhydrides
Patent holdings for IPC class D21C 3/04
Total number of patents in this class: 252
10-year publication summary
|
20
|
15
|
17
|
6
|
17
|
59
|
17
|
19
|
22
|
8
|
| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| SixRing Inc. | 179 |
62 |
| GranBio Intellectual Property Holdings, LLC | 125 |
25 |
| API Intellectual Property Holdings, LLC | 77 |
10 |
| UPM-Kymmene Corporation | 1005 |
7 |
| Valmet AB | 565 |
5 |
| Uni-Charm Corporation | 600 |
4 |
| Leaf Sciences Pty Ltd | 4 |
4 |
| New Energy Blue LLC | 15 |
4 |
| BASF SE | 21318 |
3 |
| NORAM Engineering and Constructors Ltd. | 29 |
3 |
| IFG Technologies, LLC | 13 |
3 |
| Amppc Finland Oy | 5 |
3 |
| International N&h Denmark ApS | 445 |
3 |
| The Regents of the University of Michigan | 5051 |
2 |
| Andritz AG | 248 |
2 |
| Archer Daniels Midland Company | 1072 |
2 |
| Billerud AB | 166 |
2 |
| Ch-bioforce Oy | 25 |
2 |
| Clean Chemistry, Inc. | 40 |
2 |
| Compagnie Industrielle de La Matiere Vegetale - Cimv | 19 |
2 |
| Other owners | 102 |