69
/ 100
Mostly True
United Kingdom
British spies used sperm as invisible ink during World War I, but stopped due to the smell.
Infact verdict: Mostly True (69/100).
The claims about British spies using semen as invisible ink during World War I are supported by multiple sources, including a fact-check by Snopes, which rated the claim as true. The method was indeed used because semen did not react to iodine vapor tests, making it effective for secret communication. However, the practice was discontinued due to the smell, as confirmed by both Snopes and other web sources.
How is this score determined? →Individual claims
73
Mostly True
History
British spies used sperm as invisible ink during World War I.
Snopes rated this claim as true, confirming that British spies used semen as invisible ink during World War I. This is corroborated by multiple web sources, including articles and historical accounts.
Fact Check Score
52
Fact Check Weight
40
Web Consensus Score
85
Web Consensus Weight
30
Source Quality Score
85
Source Quality Weight
15
Llm Reasoning Score
90
Llm Reasoning Weight
15
Llm Reasoning Score Raw
90
Weighted Total
73
Evidence Summary
1 fact-check match (Snopes: True), 3 web sources
70
Mostly True
History
The method of using semen as invisible ink worked.
The method was effective because semen did not react to iodine vapor tests, which was a common detection method at the time. This is supported by Snopes and other sources.
Fact Check Score
52
Fact Check Weight
40
Web Consensus Score
80
Web Consensus Weight
30
Source Quality Score
80
Source Quality Weight
15
Llm Reasoning Score
85
Llm Reasoning Weight
15
Llm Reasoning Score Raw
85
Weighted Total
70
Evidence Summary
1 fact-check match (Snopes: True), 3 web sources
63
Mostly True
History
The use of semen as invisible ink was ceased because of the smell it produced.
The practice was discontinued due to the smell, as confirmed by Snopes and other sources. This aligns with historical accounts of the method's drawbacks.
Fact Check Score
52
Fact Check Weight
40
Web Consensus Score
75
Web Consensus Weight
30
Source Quality Score
75
Source Quality Weight
15
Llm Reasoning Score
80
Llm Reasoning Weight
15
Llm Reasoning Score Raw
80
Weighted Total
63
Evidence Summary
1 fact-check match (Snopes: True), 3 web sources
