If you want the full version and license for commercial use,
you can purchase here :

https://staircaselab.com/product/london-signature/

File Font Version : 

1. London Signature.otf
2. London Signature.ttf
3. London Signature.woff
4. London Signature Italic.otf
5. London Signature Italic.ttf
6. London Signature Italic.woff