We thank both referees for their positive opinions and constructive comments that led us to improve the paper. Among other points, we also followed some their suggestions on reduction of the length and/or better organization of the paper. In particular, we moved several figures that were not necessary to be presented in the main paper to the Electronic Supplementary Information, and we moved the section „Albedos, colors and taxonomic classes“ to appendix. However, we don’t think that splitting the paper into two as suggested by Referee 2 would be good, as we think that many readers will actually like to see both the data and their interpretations in one paper. Also, moving the entire Section 3 to appendix wouldn‘t look good to us, as the (mostly short) paragraphs for the selected 35 pairs highlight some particularly interesting data and findings that we believe are good to be mentioned in the main text of the paper. Our responses to the individual points raised by the referees follow.

R1: p. 7, line 15, I’m not sure understand the limits for velocity and separation. As written it is at best ambiguous, does “5 – 10RHill” mean “five minus ten” or a range “five to ten,” or something else?  If I understand what seems to be suggested in the text that follows, what is meant is that for
younger pairs, the constants 5 and 2 are used, for older families, 4 and 10. If that is correct, then
maybe what should be written is “r_rel <= (5 or 10)R_Hill and v_rel <= (2 or 4)v_esc,” followed by the explanation of when the smaller or larger constants are taken.
A: Changed as the referee suggested.

R1: p. 8, top paragraph above Sect. 3, the age estimation and uncertainty range are well described,
and tabulated in Table 1. Since the error ranges vary so much case to case, and are sometimes
highly asymmetric, it would be good to list the uncertainty ranges in the text wherever the
estimated (50th percentile) age is stated. Perhaps the histogram plots could have arrows
indicating the minimum, median, and maximum values of age.
A: Following the referee’s suggestion, we give the estimated ages including their uncertainties in the subsections on individual asteroid pairs in Section 3 where they are mentioned. (We note that we removed the notes on the estimated ages in some subsections where they were not particularly important to be mentioned, to make the text more readable and compact.)

R1: p. 28, sect. 3.11, P1, “p = 3.0108±0.0003 h…” units missing; p. 30, sect. 3.14, “orbital period
81.19 ± 0.02 h…” units missing. There are no doubt other cases, I have not checked all carefully. All text should be checked for missing units.
A: The missing units added.

R1: Some of the encounter histograms (e.g., Fig. 23) are presented in the main paper, while others
are relegated to Suppl. Why? Perhaps all but a sample of a couple could be moved to Suppl.,plus those with anomalous shapes, e.g. Figs. 12, 22.
A: Our intention was to present in the main text several encounter histograms for certain pairs where the clone orbit integrations or estimated ages were of some specific interest, while presenting most of them in the Electronic Supplementary Information. Following your suggestion, we now moved several more of the encounter histograms to the SI, effectively saving some space in the main paper, and leaving there only the histograms for 1741-258640 (to show it for the first pair presented) and 46829-2014VR4 (to illustrate the point about the backward clone integrations discussed in Section 3.22).

R1: p. 50, sect. 3.31, a word or two missing, maybe should read “…high estimated separation time of about 1 Myr…”
A: The missing word added.

R1: In Fig. 52, p. 61, the albedo scale and binning might be better in, well, geometric units. With the linear units used, a bin width of 0.03 at albedo 0.06 spans a factor of 2 in albedo, whereas at 0.5 albedo, 0.03 is only a width of about 6% albedo. The numbers are so low at the extremes that maybe it hardly matters, but I’d suggest about ten bins spanning from .05 to .5 with bin widths of a factor of ~1.25, e.g. bin boundaries at .050 .063 .079 .100 .126 .158 .199 .251 .316 .397 .500.
A: We agree with that it might be good for some uses to show the albedo data on logarithmic scale.  For this paper, it hardly matters and we keep the plot (now Fig. B.1) unchanged. However, we will show asteroid albedo data on logarithmic scale in our future papers as appropriate.

R1: Fig. 54, p. 62, and description on p. 60, it is indicated that the albedos and colors plotted are for
the primary object. In cases where you have the data (either albedo, color, or both), it would be
good to plot in some way the data for secondaries, to show that they are close to the same, or
note where they aren’t.
A: There are only two asteroid pairs for which we got albedos for both members: 2110-44612 and 4905-7813. They perfectly agree (as do their color indices), and we add notes on it at the ends of Sections 3.2 and 3.5. In several other pairs where we got the color indices for both members, we see that they agree to within 2 sigma, except for the pair 54041-220143 on which we comment in Section 3.26. We also added a footnote on it to Appendix B. We don’t think that it is needed to add the data on the two secondaries (44612) and (7813) to Fig. B.3.

R1: p. 74, description of Fig. 59, mention the Maclaurin and Jacobi plot lines, maybe text could read “Also plotted are the size ratios of the Maclaurin (green line at top) and Jacobi (purple curve)
ellipsoids.”
A: Sentence amended as suggested.

R1: In Appendix A, p. 87, It might be good to define the columns in Table A.1 before discussing the
details for the asteroids. In particular, chi^2_red is mentioned for the solutions before it is defined in
the table description, and in fact is not really defined at all. It would be good to define just what
chi^2_red is a measure of, and also the column D; what measure is that based on? And lastly,
presumably the ten or so measurements of each of the asteroids were taken over some range of
time. Did you back-compute the rotational view at the times of the observations for the TPM?
A: We amended the text of Appendix A following the referee’s comments.
 
R1: In appendix C, p.95, is the given probability of a spurious match that of any one individual asteroid having another asteroid that close in element space, or is the probability that any one out of the 100,000 or more would have another asteroid that closely matched? That needs to be stated clearly, and if it is the probability that any one asteroid will have another that close, then of course one should expect out of 100,000 there should be many spurious matches at the 1-5% probability level, and even below.
A: We write it there better now, stating that it is the P_2/N_p as defined in Pravec and Vokrouhlicky (2009).

R1: I found Sup. Figs. 1 and 2, the plots of pole positions for (2110) and (44612), quite revealing and showed clearly that the poles differ mainly by precession to their current positions. I think including these in the main text might be good both for making this point and for including at least one pair of pole position plots in the main paper.
A: We leave the two plots (now Suppl. Figs. 2 and 3) in the SI, as we didn’t want to expand the main paper and we thought that just discussing them in the text of the main paper is sufficient.

R2: I will raise a potential issue with the pair age estimation procedure. I am not sure that the choice to use median statistics is most appropriate. My suggestion would be to use modal statistics instead with an appropriate choice of bin size—perhaps chosen such that more than half of the occupied bins have more than one close encounter event. As I examine each of the encounter distributions, I note that the median statistics typically over-estimate the encounter time relative to the most occupied bin, sometimes significantly. The distributions are generally very skewed with tails that stretch deep into the past. Given that chaos takes time to act, these oldest encounters are the least accurate but the median statistics weight them the same as the earliest encounters for which chaos had the shortest period of time to act. Figure 1 is a good example of this behavior.
A: We understand the referee‘s concern about the median time being systematically shifted towards larger age compared to the peak of the distribution. On the other hand, note that we use a finite number of clones in our integrations. Their faster dispersal along the respective orbits at later times (occupying then arbitrary values of the mean anomaly) may make it more difficult to represent larger ages in our simulation. In other words, the true possibility of later ages may be partly underestimated with the statistics of a finite number of clones. So in reality the later age-solutions are not only plausible, but their statistical weight is typically underestimated by the backward orbital clone integrations. In this situation, our method of providing the median age seems to us the most objective; referring the age to the peak of the distribution would bias the estimate to the young age solutions that have a higher probability to be obtained by the backward orbital clone integrations method.

R2: Also regarding the pair identification method, the mean orbital elements from AstDyS are averaged over 2 Myr but this is older than many of the pairs discovered by this method, so a lot of the orbital history data used to compute the proper elements is fictitious in more than one way. Is there a possibility that pairs are not being found by this choice?
A: We think that there is a slight confusion in the comment by the referee. What he or she seems to speak about (2 Myr "averaging") relates to the synthetic proper elements provided by AstDyS. The mean elements have just the short-period orbital oscilations eliminated analytically and are thus not associated with any such long timescale. As shown by Rozek et al. (2011, MNRAS 412, 987), the mean elements are fairly suitable for definition of the pair distance in the 5-D space of the orbital elements (a, e, i,Omega, omega). For pairs on rather stable orbits (weak chaos), the distance defined using the mean elements is rather stable on a ~1 Myr timescale (see Fig. 2 in Rozek et al.). So there are no such worries about the pair identification by using the mean orbital elements. Things become obviously more difficult when the orbits are chaotic or when the components in the pair are very small, such that the Yarkovsky thermal accelerations produce stronger divergence of the orbits.

R2: For a number of the pair age distributions, you find thousands of encounters. Is it possible that the 5 Hill radius and 2 times the escape velocity cut-off is too generous? How would reducing these cut-offs refine (or not) the ages? In other words, is the analysis sensitive to this choice? Relatedly, what was the measure of “orbital chaocity” that was used to adjust the criteria to 10 Hill radii and 4 times the escape velocity for some targets. Also, I think it should be clearly stated in the tables which criteria were used for which pairs.
A: In the case of good age solutions, the different criteria (5 Hill radii/2 times the escape velocity or 10 Hill radii/4 times the escape velocity) provide practically the same results, only a number of converging clones is higher for more relaxed limits. In the case of chaotic orbits or for old pairs, the tighter limits provide just too few converging cases. Note that this problem is again related to the limited number of clones that we use. For small primaries, the Hill radius may be just a few hundered kilometers. It is quite demanding to let the clones approach that close to each other. Consider, for instance, a pair in the inner main belt. Even for a tight case, the Keplerian shear smears the clones along the whole orbit in ~ 30-50 kyr (and the Yarkovsky accelerations may do it even a little bit faster). The orbital circumference is ~ 2.2*10^9 km, so if our 10^3 clones were distributed evenly, their characteristic separation would be ~ 2.2*10^6 km. Assume 10 Hill radii is ~ 10^4 km, so the separation would amount to ~ 220 times that value (and this is just naively assuming aligned inclinations, eccentricities, nodes and perihelia of the orbits). If we want some of the clones to result in convergence, and recalling that we test the relative configurations with even the high cadence of 10 days, we note that the excercise is rather non-trivial. The characteristic bins in time used in our age-distribution histograms should contain typically 7*10^5 testing trials. With 10^3 clones, spaced typically as mentioned above, we would ideally expect 1-10 successes every trial, thus ~5*10^6 in the optimum bins of the age solution distribution. But, this is largely simplified, by not taking into account eccentricity and inclination differences of the orbits. The 10^4 km zone of 10 Hill spheres represents an effective inclination difference of ~ 1.6*10^-3 degree, for instance. The osculating inclinations of typical asteroid orbits oscillate by a fraction of degree, and similar effects apply to the eccentricity. Naively assuming random distributions in the three dimensions (representing orbital along-track, radial, i.e. eccentricity effect, and normal, i.e. inclination effect), the chance to have a success in one trial drops to ~10^2-10^3, still a reasonable number for drawing statistical conclusions. Data in Fig. 2 show that very good solutions may reach much better success, those shown in Fig. 16 confirm the estimate from more spread population of clones given above. In conclusion: very good orbits may use 5 Hill radii, but often we need 10 Hill radii. These order-of-magnitude estimates show that optimistically insisting on the ideal case of convergence criterion of 1 Hill radius cannot be easily matched with our set of 10^3 clones for a pair member. Obviously, increasing the number of clones by a factor 100-1000 would help, but then the CPU requirements would start overpassing our capabilities.

R2: One measure of the accuracy of the backward integrations is to plot d_mean vs the pair age. Since d_mean should be very low, there should be a trend of d_mean increasing with pair age as this information is lost to chaos. 
A: We added a plot of the pair age vs d_mean (Fig. 1 in the revised paper) and a paragraph on it to the end of Section 2.

R2: In at least one case, the paper mentions d_prop. What is this? And how is it different than d_mean?
A: We changed the first sentence of Section 3.5 to describe it explicitly.

R2: Myhrvold (2018) has raised issues with WISE diameters in the past, so highlighting which diameters are yours and which rely on WISE data in the table would be helpful.
A: There is only a very weak sensitivity of the WISE diameters on the (mostly inaccurate) absolute magnitudes they used. Our revision of the D and p_V data with our accurate absolute magnitudes basically led just to (often significant) revisions of the p_V values. The diameters remained practically unchanged (remained well within their error bars). We report on what are our revised D values and what are the original WISE diameter values in the text of the paper or the SI, but we don’t think that it is needed to distinguish between them in Table 1.

R2: In at least one case (3.22), the paper calculates the probability that the orbital distance is random. How was this calculation done?
A: We added reference on the method to the Section 3.22.

R2: The precession coefficient alpha is used on page 64 without being introduced. In fact, there is a lot missing from the description of the spin evolution model and it would be very difficult to reproduce your calculations as you have done them. While Breiter et al. (2005) may contain the details, its necessary for this paper to at least introduce what that model contains including the governing equations of motion. This is another reason to break this analysis off into another paper.
A: We could give a more thorough description and discussion there, but it would lead to a significant lengthening of the paper. Rather, we don’t think that it’s necessary. (And we prefer to don’t do a separate paper on the spin evolution at present, rather we want to wait with that for when spin vector data are available for a larger sample of asteroid pairs in the future.) The concept of precession constant is one of the fundamentals in dynamical astronomy and we think that readers of the paper will be familiar with it. Though, in order to comply with the referee's suggestion, we briefly recall its definition. However, we do not recall secular equations for the spin evolution, which would unnecessarily extent the text. Not only they are given in detail in Breiter et al. (2005), but applications for asteroid dynamics were discussed in detail in the referenced papers of Vokrouhlicky et al. (2006) or Vrastil and Vokrouhlicky (2015). An interested reader may give a look at it in those papers.

R2: The analysis in section 6.1 is really interesting and important since it represents a possible method to look back in time to what these objects looked like prior to fission. I think it would be very helpful at the end of this section to give some example asteroids with these predicted aspect ratios (or mention if the aspect ratios are so extreme that no examples exist).
A: We added a footnote to the last paragraph of Section 6 commenting on it.

R2: Also, in the analysis the pair members are assumed to be spheres in the present day, correct? However, can’t the observations be used to better constrain this assumption?
A: We plan to pursue this in the future. However, as there is incomplete information on the asteroid shapes, we do not pursue this further now. We do note how the curves would trend taking these situations into account, and we feel that this is sufficient for the initial analysis we present in this paper.

R2: Figs 58 and 61 seem repetitive in a paper with 60+ figures.
A: The two figures (now Figs. 34 and 37 in the revised paper) show the original data and the „corrected“ data (after hypothetical ejection of the orbiting secondaries), respectively. As such, we need to present them both.

R2: The analysis in section 6.2 is really compelling. I think the authors should note that the alternative hypothesis put forward in the last paragraphs is not mutually exclusive with the one advanced in the prior paragraphs.
A: We added a sentence at the end of the section pointing out that.