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Therac-25 Case

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At one point in its interactions with the user groups, AECL found itself being asked for the source code used in the Therac 25 software. AECL claimed that it had proprietary rights to the software and would not make it public. This is another case of two values coming into conflict. A concern for safety suggests that it would be helpful to open the source code to inspection by the FDA or its agents or by the user groups. But to force this openness would violate the property rights of the owner of the software, AECL. One suspects that AECL’s refusal to open the code to inspection is a defensive move based on avoiding liability rather than an attempt to protect the value of the intellectual property. But if close inspection showed the software to be poorly designed, the value of the software would surely diminish. Is this a case in which we want to uphold property rights? There may in fact be some case here for an "open software" standard to protect public safety.

The ImpactCS grid suggests we identify several levels of social analysis for each ethical issue. In this case we have interaction among those levels. The public (ideally, represented by the FDA) was placed at great risk by the software. What claims are there that the cancer treatment facilities and the FDA can make regarding the value of their being able to inspect the design and logic of the software? What claims can patients (or their surviving families) make regarding the validity of the claim by AECL to keeps its software a trade secret? So, in order to understand the property issue correctly, we need to look at claims made at many levels: national, organizational, and individual.

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