What patent concerns must be considered when using Bouncy Castle?

How to correctly use CATransform3D

I tried to create a CATransform3D, but got it wrong. The following code does what I want, using key-values:
        [_transitionLayer setValue:[NSNumber numberWithFloat:metrics.translationPointsX] forKeyPath:@"sublayerTransform.translation.x"];
        [_transitionLayer setValue:[NSNumber numberWithFloat:metrics.radians] forKeyPath:@"sublayerTransform.rotation.y"];
        [_transitionLayer setValue:[NSNumber numberWithFloat:metrics.translationPointsZ] forKeyPath:@"sublayerTransform.translation.z"];
And here's how I tried to set it up doing CATransform3D:
CATransform3D subLayerTransform = CATransform3DMakeTranslation(0, 0, 0);
subLayerTransform = CATransform3DTranslate(subLayerTransform, metrics.translationPointsX, 0, 0);
subLayerTransform = CATransform3DRotate(subLayerTransform, metrics.radians, 0, 1, 0);
subLayerTransform = CATransform3DTranslate(subLayerTransform, 0, 0, metrics.translationPointsZ);
How can I create the matching transform to the one using the key-paths ?What patent concerns must be considered when using Bouncy Castle?

Given that Bouncy Castle is an Open Source project, it's entirely possible that the contents contains implementations protected by various patents.
Since it's possible for the patent holder to sue the developer and the end user of such software, what aspects of the software are "known safe" or "known unsafe" with regard to unencumbered use by patents?
Example
Many authenticated encryption modes for Block Ciphers are protected by various patents. Examples of such modes are XCBC, IACBC, IAPM, OCB, EAX, CWC, CCM, and GCM.
Up until January 2013, OCB mode had a restricted license for commercial implementations, and in theory could have put them at risk of a lawsuit.
Even though the OCB mode IP license has been relaxed somewhat, it's still important to know which implementations are safe and unsafe for general use