Rosalind Franklin did not share the Nobel Prize for the DNA structure because:

1. The prize for the structure of DNA was awarded some years after the model was published. 2. Franklin's X-ray diffraction work was central to that model. 3. Unfortunately, by then Franklin had died, and Nobel prizes are not awarded posthumously. 4. That rule, rather than any judgement about her contribution, is what excluded her. 5. Her data were used, which is exactly why the omission is remembered. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 14 'DNA Structure and Function', sections 14.1-14.6_