@box/box-windows-sdk-v2 v6.4.0 release note

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+CSharp

content/2025/12-19-box-windows-sdk-v640-released.md

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+---
+applied_at: '2025-12-19'
+applies_to:
+  - sdks
+  - dotnet
+is_impactful: true
+is_new_feature: true
+release_source_url: 'https://github.com/box/box-windows-sdk-v2/releases/tag/v6.4.0'
+collapse: true
+---
+
+# Box Windows SDK `v6.4.0` released
+
+### **New Features and Enhancements:**
+
+* **boxsdkgen:** add Metadata Taxonomies api (box/box-openapi[#569][1]) ([#1329][2]) ([`5908cf2`][3])
+* **boxsdkgen:** text input validation for Box Sign (box/box-openapi[#568][4]) ([#1323][5]) ([`d094726`][6])
+* **boxsdkgen:** Treat `nullable` fields as Optional (box/box-codegen[#906][7]) ([#1333][8]) ([`1b61619`][9])
+
+### **Bug Fixes:**
+
+* **boxsdkgen:** add taxonomy to Metadata Field (read) definition (box/box-openapi[#572][10]) ([#1343][11]) ([`8152df7`][12])
+* **boxsdkgen:** Fix convert to long in CSharp (box/box-codegen[#911][13]) ([#1354][14]) ([`25433e5`][15])
+
+[1]: https://github.com/box/box-windows-sdk-v2/issues/569
+
+[2]: https://github.com/box/box-windows-sdk-v2/issues/1329
+
+[3]: https://github.com/box/box-windows-sdk-v2/commit/5908cf22ffeb8c14bb727d44fd58b57a3f7d6ea0
+
+[4]: https://github.com/box/box-windows-sdk-v2/issues/568
+
+[5]: https://github.com/box/box-windows-sdk-v2/issues/1323
+
+[6]: https://github.com/box/box-windows-sdk-v2/commit/d094726711e982b889d6caa4378736cb3dde673a
+
+[7]: https://github.com/box/box-windows-sdk-v2/issues/906
+
+[8]: https://github.com/box/box-windows-sdk-v2/issues/1333
+
+[9]: https://github.com/box/box-windows-sdk-v2/commit/1b61619142c0896856791a12cae709d5d0d138f6
+
+[10]: https://github.com/box/box-windows-sdk-v2/issues/572
+
+[11]: https://github.com/box/box-windows-sdk-v2/issues/1343
+
+[12]: https://github.com/box/box-windows-sdk-v2/commit/8152df75926b0ee5bad504b0707adb31f099ef9b
+
+[13]: https://github.com/box/box-windows-sdk-v2/issues/911
+
+[14]: https://github.com/box/box-windows-sdk-v2/issues/1354
+
+[15]: https://github.com/box/box-windows-sdk-v2/commit/25433e5a1044cc36ebdb604b4ead55d0db5d1158