And if so, what was the highest score so far?
Some news articles suggest only parts of tests were aced.
Update since people censored this question and closed it. There was an AI that has taken an IQ test and scored similar to a 4 year old.
The AI system which they used is ConceptNet, an open-source project run by the MIT Common Sense Computing Initiative. Results: It scored a WPPSI-III VIQ that is average for a four-year-old child, but below average for 5 to 7 year-olds
We administered the Verbal IQ (VIQ) part of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) to the ConceptNet 4 AI system. The test questions (e.g., "Why do we shake hands?") were translated into ConceptNet 4 inputs using a combination of the simple natural language processing tools that come with ConceptNet together with short Python programs that we wrote. The question answering used a version of ConceptNet based on spectral methods. The ConceptNet system scored a WPPSI-III VIQ that is average for a four-year-old child, but below average for 5 to 7 year-olds. Large variations among subtests indicate potential areas of improvement. In particular, results were strongest for the Vocabulary and Similarities subtests, intermediate for the Information subtest, and lowest for the Comprehension and Word Reasoning subtests. Comprehension is the subtest most strongly associated with common sense. The large variations among subtests and ordinary common sense strongly suggest that the WPPSI-III VIQ results do not show that "ConceptNet has the verbal abilities a four-year-old." Rather, children's IQ tests offer one objective metric for the evaluation and comparison of AI systems. Also, this work continues previous research on Psychometric AI.
Update. A robot has passed the Japanese college entrance test and has an 80% chance of being accepted. Since it scored more than the average, that would make the IQ > 100, especially since college applicants have an IQ greater than average, and especially since Japanese are smarter than average humans. http://gizmodo.com/an-ai-program-in-japan-just-passed-a-college-entrance-e-1742758286
The Wall Street Journal reports that the program, developed by Japan’s National Institute of Informatics, took a multi-subject college entrance exam and passed with an above-average score of 511 points out of a possible 950. (The national average is 416.) With scores like that, it has an 8 out of 10 chance of being admitted to 441 private institutions in Japan, and 33 national ones.