True or False?
The answer is False. Investors do not have to speculate. The profit opportunity can be realized through arbitrage and investors generally will not choose to bear risk if they can avoid it. Risk can be avoided by making a covered forward sale of the funds into which one shifts to take advantage of the arbitrage opportunity. Notice that the question assumes no differential risk of holding the Deutschmark and franc denominated bonds because they are issued by the same country by the same company.
While an expected gain might well be made from taking an uncovered position here, a wise investor will keep her arbitrage activities separate from her speculative activities. The proper procedure would be to conduct arbitrage whenever such opportunities present themselves. Then, if one believes that the difference between forward and expected future spot rates on a contract of a particular maturity exceeds one's evaluation of the foreign exchange risk from taking an uncovered position, one can go short in the currency one expects to devalue by more than indicated by the risk-adjusted forward discount. The arbitrage and speculative transactions involve two separate portfolio management decisions, each of which must be judged on its own.
We might also mention the possibility that two securities issued by the same company in two different currencies probably can never be identical. The interest paid and time to maturity may well be the same, but there is always the possibility that the government in the country of issue can pass laws restricting the disposal of interest received in a particular currency.