What is not true for genetic code?

The general features of genetic code are : (i) The genetic code is written in linear form, using the ribonucleotide bases that compose mRNA molecule as letters. (ii) Each word of codon consists of three letters, ie, the codon is triplet. (iii) The genetic code inside the cell medium is said to be non-ambiguous. (iv) The code is degenerate, $i e$, a given amino acid can be specified by more than one codons. (v) The codon contains 'start' and 'stop' signals. (vi) The code is said to be commaless. (vii) The code is non-overlapping.