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tokens: by the two profiles provided by the IceCube Collaboration, instead of an electromagnetic light curve. The first one (denoted in the following as “Gaussian flare’) is modeled by a Gaussian signal centered on MJD 57004 and with a standard deviation σ = 55.0 days. We considered a period ±5 σ wide, corresponding to 550 flaring days. The second one (referred to as “box flare”) assumes a box-shaped flare starting at MJD 56937.81 and ending at MJD 57096.21, corresponding to 158.40 flaring days. The time-dependent analysis first defines the values of selection cuts that, assuming a power-law neutrino spectrum for the signal, optimizes the Model Rejection Factor. Three different spectral indexes for the neutrino spectrum have been considered ( γ = 2.0, 2.1, and 2.2), and the cut parameters to be optimized are the maximum reconstructed neutrino zenith angle, θ , and the quality of reconstructed tracks, Λ. The resulting optimized set of cuts for the three considered spectral indexes are cos θ > −0.15 and Λ > −5.6. For comparison, the corresponding cuts for the time-integrated search reported in Section 3 are and Λ > −5.2. This means that the time-dependent analysis allows for more downward-going neutrino candidates and tracks with a lower reconstruction quality parameter; refer to Figure 2 of Albert et al. ( 2017a ). According to this set of cuts, the expected background during the box flare has been estimated as 0.04 (4) events within 05 (5°) from the source. This is a factor ∼4 larger than that determined for the time-integrated search. The background increases because a larger fraction of atmospheric muons is mis-reconstructed and because more low-energy atmospheric neutrinos are included. Thanks to the reduced observational time window, the method allows the presence of lower energy cosmic neutrinos and de facto corresponds to an analysis sensitive to a softer neutrino energy spectrum. After the optimization, the data have been unblinded. The results are compatible with the expectation from the atmospheric background, and no signal has been found during either of the considered flares. Within 2° from the source, 10 background events are expected during the analyzed period, while 13 events have been found in data. None of them lie within either of the two considered flaring periods. From these null results, 90% C.L. upper limits have been derived for the neutrino flux. For an E −2.0 ( E −2.1 ) [ E −2.2 ] spectrum they correspond to a normalization factor of GeV −1 cm −2 s −1 for the Gaussian-shaped period. The energy range containing the 5%–95% of the detectable flux is 2.0 (1.3) [1.0] TeV–3.2 (1.6) [1.0] PeV. For the box-shaped period, the flux normalization factors are a factor of 3.3 higher. 5. Conclusions The GCN circular (IceCube Collaboration 2017 ) on the EHE neutrino candidate event, IC170922A, promptly triggered a search for neutrino candidates in the ANTARES online data stream. The position of the IC170922A event at the location of the