multiple consumers per kinesis shard

I read you can have multiple consumer apps per kinesis stream.

http://docs.aws.amazon.com/kinesis/latest/dev/developing-consumers-with-kcl.html

however, I heard you can only have one consumer per shard. Is this true? I don't find any documentation to support this, and can't imagine how that could be if multiple consumers are reading from the same stream. Certainly, it doesn't mean the producer needs to repeat content in different shards for different consumers.